簡約 tan^2(a)(2cos^2(a)+sin^2(a)-1)

解

簡約

tan^{2} (a) (2 cos^{2} (a) + sin^{2} (a) - 1)

sin^{2} (a)

解答ステップ

tan^{2} (a) (2 cos^{2} (a) + sin^{2} (a) - 1)

ピタゴラスの公式を使用する:

1 = cos^{2} (x) + sin^{2} (x)

1 - sin^{2} (x) = cos^{2} (x)

= tan^{2} (a) (2 cos^{2} (a) - cos^{2} (a))

cos^{2} (a) tan^{2} (a) = sin^{2} (a)

= sin^{2} (a)

因数

2 cos^{2} (a) - cos^{2} (a) : cos^{2} (a)

= sin^{2} (a)