{"id":2218,"date":"2025-12-24T17:19:15","date_gmt":"2025-12-24T08:19:15","guid":{"rendered":"https:\/\/math-travel.com\/?p=2218"},"modified":"2026-02-11T16:39:38","modified_gmt":"2026-02-11T07:39:38","slug":"asinbcos","status":"publish","type":"post","link":"https:\/\/math-travel.jp\/math-2\/asinbcos\/","title":{"rendered":"\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306e\u3084\u308a\u65b9\u3068\u30b3\u30c4\u30105\u30b9\u30c6\u30c3\u30d7\u3011\u3067\u6700\u5927\u30fb\u6700\u5c0f\u554f\u984c\u3082\u6016\u304f\u306a\u3044"},"content":{"rendered":"\n
\u300c\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u304c\u3088\u304f\u5206\u304b\u3089\u306a\u3044\u300d<\/span> \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u304c\u5206\u304b\u308a\u307e\u305b\u3093<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n \u4ee5\u4e0b\u304c\u4eca\u56de\u89e3\u8aac\u3059\u308b\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u516c\u5f0f<\/span>\u3067\u3059\u3002<\/p>\n\n\n\n \\(a\\)\u3068\\(b\\)\u306e\u3044\u305a\u308c\u304b\u304c\\(0\\)\u3067\u306a\u3044\u3068\u304d<\/p>\n\n\n\n \\[a \\sin \\theta+b \\cos \\theta=\\sqrt{a^{2}+b^{2}} \\sin (\\theta+\\alpha)\\]<\/p>\n\n\n\n \u305f\u3060\u3057, \\(\\alpha\\)\u306f\\(\\displaystyle \\sin \\alpha=\\frac{b}{\\sqrt{a^{2}+b^{2}}},\\cos \\alpha=\\frac{a}{\\sqrt{a^{2}+b^{2}}}\\) \u3092\u6ee1\u305f\u3059\u89d2\u5ea6\u3068\u3059\u308b\u3002<\/p>\n<\/div><\/div>\n\n\n\n \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u3063\u3066\u96e3\u3057\u305d\u3046\u306b\u898b\u3048\u307e\u3059\u3088\u306d\u3002<\/p>\n\n\n \u5b9f\u306f\u305d\u3093\u306a\u3053\u3068\u306a\u3044\u3088\uff01<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n \u516c\u5f0f\u306e\u898b\u305f\u76ee\u306f\u8907\u96d1\u3067\u3059\u304c\u3001\u8a3c\u660e\u3084\u4f7f\u3044\u65b9\u306f\u4ed6\u3068\u6bd4\u3079\u3066\u3082\u30b7\u30f3\u30d7\u30eb\u3067\u3059\u3002<\/p>\n\n\n\n \u305f\u3060\u3001\u5165\u8a66\u3067\u3082\u4f7f\u3046\u91cd\u8981\u306a\u516c\u5f0f<\/span>\u306a\u306e\u3067\u78ba\u5b9f\u306b\u6291\u3048\u3066\u304a\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n \u672c\u8a18\u4e8b\u3067\u306f\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u516c\u5f0f\u306b\u3064\u3044\u3066\u89e3\u8aac<\/span>\u3057\u307e\u3057\u305f\u3002<\/p>\n\n\n\n \u56f3\u3092\u7528\u3044\u3066\u89e3\u8aac\u3057\u3066\u3044\u308b\u306e\u3067\u3001\u305c\u3072\u6700\u5f8c\u307e\u3067\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/p>\n\n\n \u6c17\u306b\u306a\u308b\u898b\u51fa\u3057\u3092\u30af\u30ea\u30c3\u30af\u3057\u3066\u3001 \u307e\u305a\u306f\\(\\sin\\)\u306e\u5408\u6210\u516c\u5f0f\u304b\u3089\u89e3\u8aac\u3057\u307e\u3059\u3002<\/span><\/p>\n\n\n\n \\(a\\)\u3068\\(b\\)\u306e\u3044\u305a\u308c\u304b\u304c\\(0\\)\u3067\u306a\u3044\u3068\u304d<\/p>\n\n\n\n \\[a \\sin \\theta+b \\cos \\theta=\\sqrt{a^{2}+b^{2}} \\sin (\\theta+\\alpha)\\]<\/p>\n\n\n\n \u305f\u3060\u3057, \\(\\alpha\\)\u306f\\(\\displaystyle \\sin \\alpha=\\frac{b}{\\sqrt{a^{2}+b^{2}}},\\cos \\alpha=\\frac{a}{\\sqrt{a^{2}+b^{2}}}\\) \u3092\u6ee1\u305f\u3059\u89d2\u5ea6\u3068\u3059\u308b\u3002<\/p>\n<\/div><\/div>\n\n\n\n \\(\\sin \\theta+\\cos \\theta\\)\u3092\\(\\sin\\)\u3067\u5408\u6210\u3059\u308b\u3068\u304d\u306f\u4ee5\u4e0b\u306e\u4e09\u89d2\u5f62\u3092\u63cf\u304d\u307e\u3059\u3002<\/p>\n\n\n \\(\\sin \\theta\\)\u306e\u4fc2\u6570\u21d2\u30001<\/p>\n\n\n\n \\(\\cos \\theta\\)\u306e\u4fc2\u6570\u21d2\u30001<\/p>\n\n\n\n \u3053\u306e\u5834\u5408\u306f\u3001(1,1)\u306b\u70b9\u3092\u6253\u3061\u307e\u3057\u3087\u3046\u3002<\/p>\n<\/div><\/div>\n\n\n\n \u3057\u305f\u304c\u3063\u3066\u3001<\/p>\n\n\n\n \\begin{eqnarray} \u3068\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n \u5ea7\u6a19\u5e73\u9762\u4e0a\u306b\u70b9\u3092\u53d6\u3063\u3066\u3001\u4e09\u89d2\u5f62\u3092\u30a4\u30e1\u30fc\u30b8\u3059\u308b\u3068\u89e3\u304d\u3084\u3059\u304f\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n \u5206\u304b\u3063\u305f\u3088\u3046\u306a\u5206\u304b\u3089\u306a\u3044\u3088\u3046\u306a\u2026<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n \u4f7f\u3044\u65b9\u306e\u89e3\u8aac\u3082\u3057\u3066\u3044\u308b\u304b\u3089\u305c\u3072\u8aad\u3093\u3067\u307f\u3066\u3002<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n \u6b21\u306f\\(\\cos\\)\u306e\u5408\u6210\u516c\u5f0f\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n \\(a\\)\u3068\\(b\\)\u306e\u3044\u305a\u308c\u304b\u304c\\(0\\)\u3067\u306a\u3044\u3068\u304d<\/p>\n\n\n\n \\[a \\sin \\theta+b \\cos \\theta=\\sqrt{a^{2}+b^{2}} \\cos (\\theta-\\beta)\\]<\/p>\n\n\n\n \u305f\u3060\u3057, \\(\\beta\\)\u306f\\(\\displaystyle \\sin \\beta=\\frac{a}{\\sqrt{a^{2}+b^{2}}},\\cos \\beta=\\frac{b}{\\sqrt{a^{2}+b^{2}}}\\) \u3092\u6ee1\u305f\u3059\u89d2\u5ea6\u3068\u3059\u308b\u3002<\/p>\n<\/div><\/div>\n\n\n\n \\(\\sin \\theta+\\cos \\theta\\)\u3092\\(\\cos\\)\u3067\u5408\u6210\u3059\u308b\u3068\u3001<\/p>\n\n\n\n \\begin{eqnarray} \\(\\sin\\)\u306e\u5408\u6210\u3068\u7570\u306a\u308a\u3001\u304b\u3063\u3053\u306e\u4e2d\u8eab\u304c\u30de\u30a4\u30ca\u30b9<\/span>\u306a\u306e\u3067\u6ce8\u610f\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n \u5408\u6210\u516c\u5f0f\u306e\u8a3c\u660e\u306b\u306f\u52a0\u6cd5\u5b9a\u7406\u3092\u4f7f\u3044\u307e\u3059\u3002<\/span><\/p>\n\n\n\n \u30fb\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\\(\\sin\\)<\/span><\/p>\n\n\n \u4e0a\u56f3\u304b\u3089\u4ee5\u4e0b\u306e\u3053\u3068\u304c\u3044\u3048\u307e\u3059\u3002<\/p>\n\n\n\n \\[r=\\sqrt{a^{2}+b^{2}}\\]<\/p>\n\n\n\n \\[\\displaystyle \\sin \u03b1=\\frac{b}{r} \\Leftrightarrow b=r\\sin \u03b1\\]<\/p>\n\n\n\n \\[\\displaystyle \\cos \u03b1=\\frac{a}{r} \\Leftrightarrow a=r\\cos \u03b1\\]<\/p>\n<\/div><\/div>\n\n\n\n \u3053\u3053\u3067<\/p>\n\n\n\n \\begin{eqnarray} \u3088\u3063\u3066\u3001\u8a3c\u660e\u7d42\u4e86\u3002<\/p>\n\n\n\n \u30fb\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\\(\\cos\\)<\/span><\/p>\n\n\n\n \u6b21\u306f\\(\\cos\\)\u306e\u5f62\u3092\u3057\u305f\u5408\u6210\u306e\u8a3c\u660e\u3092\u3057\u307e\u3059\u3002<\/p>\n\n\n\n \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306f\\(\\sin\\)\u306e\u5f62\u306b\u3059\u308b\u3053\u3068\u304c\u307b\u3068\u3093\u3069\u3067\u3059\u304c\u3001\\(\\cos\\)\u306e\u5f62\u306b\u3082\u5909\u5f62\u3067\u304d\u308b\u3068\u8003\u3048\u65b9\u306e\u5e45\u304c\u5e83\u304c\u308a\u307e\u3059\u3002<\/p>\n\n\n\n \\(a \\sin \\theta + b \\cos \\theta\\)\u3092\u7528\u3044\u3066\u8a3c\u660e\u3057\u307e\u3059\u3002<\/p>\n\n\n\n \\(\\cos\\)\u3067\u5408\u6210\u3059\u308b\u3068\u304d\u306f\u3001\u70b9\\(P(b,a)\\)\u3068\u3057\u307e\u3059\u3002<\/p>\n\n\n \u305d\u308c\u306b\u3088\u3063\u3066\u3001<\/p>\n\n\n\n \\[r=\\sqrt{a^{2}+b^{2}}\\]<\/p>\n\n\n\n \\[\\displaystyle \\sin \u03b1=\\frac{a}{r} \\Leftrightarrow a=r\\sin \u03b1\\]<\/p>\n\n\n\n \\[\\displaystyle \\cos \u03b1=\\frac{b}{r} \\Leftrightarrow b=r\\cos \u03b1\\]<\/p>\n<\/div><\/div>\n\n\n\n \u3053\u3053\u3067\u3001<\/p>\n\n\n\n \\begin{eqnarray} \u3088\u3063\u3066\u3001\u8a3c\u660e\u7d42\u4e86\u3002<\/p>\n\n\n \u5f0f\u5909\u5f62\u3057\u3066\u52a0\u6cd5\u5b9a\u7406\u306e\u5f62\u306b\u3057\u305f\u3093\u3067\u3059\u306d\uff01<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u3092\u3069\u306e\u3088\u3046\u306b\u4f7f\u3046\u306e\u304b\u78ba\u8a8d\u3057\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n \\(\\sqrt{3}\\sin \\theta+\\cos \\theta\\)\u3092,\\(r\\sin (\\theta+\\alpha)\\)\u306e\u5f62\u306b\u53d8\u5f62\u305b\u3088\u3002<\/p>\n\n\n\n \u305f\u3060\u3057, \\(r>0,-\\pi<\\alpha<\\pi\\) \u3068\u3059\u308b.<\/p>\n<\/div><\/div>\n\n\n\n \u305d\u3057\u3066\u3001\u5408\u6210\u3059\u308b\u969b\u306e\u4e3b\u306a\u624b\u9806\u306f\u3053\u3061\u3089<\/p>\n\n\n\n \u305d\u308c\u3067\u306f\u5177\u4f53\u7684\u306b\u6c42\u3081\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n \u89e3\u8aac<\/span><\/p>\n\n\n\n \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u3092\u3059\u308b\u305f\u3081\u306b\u3001\u659c\u8fba\u3068\u504f\u89d2\u3092\u6c42\u3081\u307e\u3059\u3002<\/span><\/p>\n\n\n\n \\(\\sqrt{3}\\sin \\theta+\\cos \\theta\\)\u306e\u5408\u6210\u306a\u306e\u3067\u3001<\/p>\n\n\n\n \\(x\\)\u5ea7\u6a19\u304c\\(\\sqrt{3}\\)\u3001\\(y\\)\u5ea7\u6a19\u304c\\(1\\)\u306e\u4e09\u89d2\u5f62\u3092\u63cf\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n \u3059\u308b\u3068\u3001\u659c\u8fba\\(r\\)\u306e\u9577\u3055\u306f\u4e09\u5e73\u65b9\u306e\u5b9a\u7406\u3088\u308a\u3001<\/p>\n\n\n\n \\[r=\\sqrt{\\sqrt{3}^{2}+1^{2}}=2\\]<\/p>\n\n\n\n \u3053\u308c\u306f\u504f\u89d2\u306e\u5927\u304d\u3055\u304c\\(\\displaystyle \\frac{\\pi}{6}\\)\u306e\u4e09\u89d2\u5f62\u3067\u3059\u3002<\/p>\n\n\n \u4e09\u89d2\u5f62\u306e\u659c\u8fba\u306e\u9577\u3055\u3068\u504f\u89d2\u304c\u5206\u304b\u308a\u307e\u3057\u305f\u3002<\/p>\n\n\n\n \u3057\u305f\u304c\u3063\u3066\u3001<\/p>\n\n\n\n \\[\\displaystyle \\sqrt{3} \\sin \\theta+\\cos \\theta=2 \\sin (\\theta + \\frac{\\pi}{6})\\]<\/span><\/p>\n\n\n\n \u3053\u308c\u3067\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u304c\u3067\u304d\u307e\u3057\u305f\u3002<\/p>\n\n\n \u601d\u3063\u305f\u3088\u308a\u3082\u7c21\u5358\u3067\u3057\u305f\uff01<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n \u4e0e\u3048\u3089\u308c\u305f\u5f0f\u304b\u3089\u56f3\u304c\u66f8\u3051\u308c\u3070\u7c21\u5358\u3060\u306d<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306b\u6311\u6226\u3057\u3066\u307f\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n\n \u6b21\u306e\u5f0f\u3092,\\(r\\sin (\\theta+\\alpha)\\)\u306e\u5f62\u306b\u53d8\u5f62\u305b\u3088\u3002\u305f\u3060\u3057, \\(r>0,-\\pi<\\alpha<\\pi\\) \u3068\u3059\u308b\u3002<\/p>\n\n\n\n (1) \\(\\sin \\theta+\\sqrt{3} \\cos \\theta\\)<\/p>\n\n\n\n (2) \\(\\sin \\theta-\\cos \\theta\\)<\/p>\n<\/div><\/div>\n\n\n \u5b9f\u969b\u306b\u624b\u3092\u52d5\u304b\u3057\u3066\u8003\u3048\u3066\u307f\u3088\u3046\uff01<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n \\(\\sin \\theta+\\sqrt{3} \\cos \\theta\\)\u306e\u5408\u6210\u3092\u8003\u3048\u307e\u3059\u3002<\/p>\n\n\n\n \u307e\u305a\u3001\u5ea7\u6a19\u5e73\u9762\u4e0a\u306b\u4e09\u89d2\u5f62\u3092\u66f8\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n \u4e09\u5e73\u65b9\u306e\u5b9a\u7406\u3088\u308a\u3001<\/p>\n\n\n\n \\begin{eqnarray} \u56f3\u304b\u3089\u504f\u89d2\u306f\\(\\displaystyle \\frac{\\pi}{3}\\)\u3060\u3068\u5206\u304b\u308b\u306e\u3067<\/p>\n\n\n\n \\[\\sin \\theta+\\sqrt{3} \\cos \\theta=2 \\sin(\\theta+\\frac{\\pi}{3})\\]<\/span><\/p>\n\n\n\n \\(\\sin \\theta-\\cos \\theta\\)\u306e\u5408\u6210\u3092\u8003\u3048\u307e\u3059\u3002<\/p>\n\n\n\n \u307e\u305a\u3001\u5ea7\u6a19\u5e73\u9762\u4e0a\u306b\u4e09\u89d2\u5f62\u3092\u66f8\u304d\u307e\u3057\u3087\u3046\u3002<\/p>\n\n\n \u4e09\u5e73\u65b9\u306e\u5b9a\u7406\u3088\u308a\u3001<\/p>\n\n\n\n \\begin{eqnarray} \u56f3\u304b\u3089\u504f\u89d2\u306f\\(\\displaystyle -\\frac{\\pi}{4}\\)\u3060\u3068\u5206\u304b\u308b\u306e\u3067<\/p>\n\n\n\n \\[\\sin \\theta – \\cos \\theta=\\sqrt{2} \\sin(\\theta-\\frac{\\pi}{4})\\]<\/span><\/p>\n\n\n\n \u4eca\u56de\u306f\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306b\u3064\u3044\u3066\u307e\u3068\u3081\u307e\u3057\u305f\u3002<\/span><\/p>\n\n\n\n \u57fa\u672c\u306f\\(\\sin\\)\u306e\u5408\u6210\u516c\u5f0f\u3092\u7528\u3044\u308b\u3002<\/p>\n\n\n\n \\(a\\)\u3068\\(b\\)\u306e\u3044\u305a\u308c\u304b\u304c\\(0\\)\u3067\u306a\u3044\u3068\u304d<\/p>\n\n\n\n \\[a \\sin \\theta+b \\cos \\theta=\\sqrt{a^{2}+b^{2}} \\sin (\\theta+\\alpha)\\]<\/p>\n\n\n\n \u305f\u3060\u3057, \\(\\alpha\\)\u306f\\(\\displaystyle \\sin \\alpha=\\frac{b}{\\sqrt{a^{2}+b^{2}}},\\cos \\alpha=\\frac{a}{\\sqrt{a^{2}+b^{2}}}\\) \u3092\u6ee1\u305f\u3059\u89d2\u5ea6\u3068\u3059\u308b\u3002<\/p>\n<\/div><\/div>\n\n\n\n \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306b\u306f\u52a0\u6cd5\u5b9a\u7406\u304c\u4f7f\u308f\u308c\u3066\u3044\u307e\u3057\u305f\u306d\u3002<\/p>\n\n\n\n \u4eca\u56de\u306f\u5408\u6210\u516c\u5f0f\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u307e\u3057\u305f\u304c\u3001<\/span>\u4e09\u89d2\u95a2\u6570\u306b\u306f\u91cd\u8981\u306a\u516c\u5f0f\u304c\u305f\u304f\u3055\u3093\u3042\u308a\u307e\u3059\u3002<\/span><\/p>\n","protected":false},"excerpt":{"rendered":" \u300c\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u304c\u3088\u304f\u5206\u304b\u3089\u306a\u3044\u300d\u300c\u4f55\u3092\u8868\u3057\u3066\u308b\u306e\uff1f\u300d\u4eca\u56de\u306f\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306b\u95a2\u3059\u308b\u60a9\u307f\u3092\u89e3\u6c7a\u3057\u307e\u3059\u3002 \u4ee5\u4e0b\u304c\u4eca\u56de\u89e3\u8aac\u3059\u308b\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u516c\u5f0f\u3067\u3059\u3002 \u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u3063\u3066\u96e3\u3057\u305d\u3046\u306b\u898b\u3048\u307e\u3059\u3088\u306d\u3002 \u516c\u5f0f\u306e\u898b\u305f\u76ee\u306f\u8907\u96d1\u3067\u3059\u304c\u3001\u8a3c\u660e […]<\/p>\n","protected":false},"author":1,"featured_media":6776,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"swell_btn_cv_data":"","footnotes":""},"categories":[35,224],"tags":[36,14,11],"class_list":["post-2218","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sincos","category-math-2","tag-36","tag-b","tag-11"],"yoast_head":"\n
\u300c\u4f55\u3092\u8868\u3057\u3066\u308b\u306e\uff1f\u300d<\/span>
\u4eca\u56de\u306f\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u306b\u95a2\u3059\u308b\u60a9\u307f\u3092\u89e3\u6c7a\u3057\u307e\u3059\u3002<\/p>\n\n\n
\u9ad8\u6821\u751f<\/span><\/div>
\u30b7\u30fc\u30bf<\/span><\/div>
\u30b7\u30fc\u30bf<\/span><\/div>
\u305c\u3072\u6700\u5f8c\u307e\u3067\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/p>\n<\/span><\/span><\/span><\/div><\/div><\/div><\/div>\n\n\n\\(\\sin\\)\u306e\u5408\u6210\u516c\u5f0f<\/h2>\n\n\n\n
<\/figure>\n<\/div>\n\n\n
\\displaystyle \\sin \\theta+\\cos \\theta&=&\\sqrt{1^{2}+1^{2}}\\sin \\left(\\theta+\\frac{\\pi}{4}\\right)\\\\
&=&\\sqrt{2}\\sin \\left(\\theta+\\frac{\\pi}{4}\\right)
\\end{eqnarray}<\/p>\n\n\n\n
\u9ad8\u6821\u751f<\/span><\/div>
\u30b7\u30fc\u30bf<\/span><\/div>\\(\\cos\\)\u306e\u5408\u6210\u516c\u5f0f<\/h2>\n\n\n\n
\\displaystyle \\sin \\theta+\\cos \\theta&=&\\sqrt{1^{2}+1^{2}}\\cos \\left(\\theta-\\frac{\\pi}{4}\\right)\\\\
&=&\\sqrt{2}\\cos \\left(\\theta-\\frac{\\pi}{4}\\right)
\\end{eqnarray}<\/p>\n\n\n\n\u5408\u6210\u516c\u5f0f\u306e\u8a3c\u660e<\/h2>\n\n\n\n
<\/figure>\n<\/div>\n\n\n
a \\sin \\theta + b \\cos \\theta&=&r\\cos \\alpha \\sin \\theta +r\\sin \\alpha \\cos \\theta\\\\
&=&r(\\sin \\theta \\cos \\alpha +\\cos \\theta \\sin \\alpha)\\\\
&=&r\\sin (\\theta + \\alpha)\\\\
&=&\\sqrt{a^{2}+b^{2}}\\sin (\\theta + \\alpha)
\\end{eqnarray}<\/p>\n\n\n\n
<\/figure>\n<\/div>\n\n\n
a \\sin \\theta + b \\cos \\theta&=&r\\sin \\alpha \\sin \\theta +r\\cos \\alpha \\cos \\theta\\\\
&=&r(\\cos \\theta \\cos \\alpha +\\sin \\theta \\sin \\alpha )\\\\
&=&r\\cos (\\theta – \\alpha)\\\\
&=&\\sqrt{a^{2}+b^{2}}\\cos (\\theta – \\alpha)
\\end{eqnarray}<\/p>\n\n\n\n
\u9ad8\u6821\u751f<\/span><\/div>\u5408\u6210\u516c\u5f0f\u306e\u4f7f\u3044\u65b9<\/h2>\n\n\n\n
\n
<\/figure>\n<\/div>\n\n\n
<\/figure>\n<\/div>\n\n\n
\u9ad8\u6821\u751f<\/span><\/div>
\u30b7\u30fc\u30bf<\/span><\/div>\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u300a\u7df4\u7fd2\u554f\u984c\u300b<\/h2>\n\n\n\n
\u30b7\u30fc\u30bf<\/span><\/div>\u7df4\u7fd2\u554f\u984c1\u306e\u89e3\u8aac<\/h3>\n\n\n\n
<\/figure>\n<\/div>\n\n\n
r&=&\\sqrt{1^{2}+\\sqrt{3}^{2}}\\\\
&=&2
\\end{eqnarray}<\/p>\n\n\n\n\u7df4\u7fd2\u554f\u984c2\u306e\u89e3\u8aac<\/h3>\n\n\n\n
<\/figure>\n<\/div>\n\n\n
r&=&\\sqrt{1^{2}+1^{2}}\\\\
&=&\\sqrt{2}
\\end{eqnarray}<\/p>\n\n\n\n\u4e09\u89d2\u95a2\u6570\u306e\u5408\u6210\u3000\u307e\u3068\u3081<\/h2>\n\n\n\n
\n