Sin²β+Sin²α+Sin²αSin²β+Cos²αCos²β 等于多少?....
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/01 04:38:59
![Sin²β+Sin²α+Sin²αSin²β+Cos²αCos²β 等于多少?....](/uploads/image/z/1077120-0-0.jpg?t=Sin%26%23178%3B%CE%B2%2BSin%26%23178%3B%CE%B1%2BSin%26%23178%3B%CE%B1Sin%26%23178%3B%CE%B2%2BCos%26%23178%3B%CE%B1Cos%26%23178%3B%CE%B2+%E7%AD%89%E4%BA%8E%E5%A4%9A%E5%B0%91%3F....)
Sin²β+Sin²α+Sin²αSin²β+Cos²αCos²β 等于多少?....
Sin²β+Sin²α+Sin²αSin²β+Cos²αCos²β 等于多少?
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Sin²β+Sin²α+Sin²αSin²β+Cos²αCos²β 等于多少?....
因为Cos²αCos²β=(1-Sin²α)*(1-Sin²β)=1-Sin²β-Sin²α+Sin²αSin²β
所以Sin²β+Sin²α+Sin²αSin²β+Cos²αCos²β
=Sin²β+Sin²α+Sin²αSin²β+(1-Sin²β-Sin²α+Sin²αSin²β)
=1+2Sin²αSin²β
因此,你确定题目没写错?