簡約 (cos^2(x)-sin^2(x))/(cos^2(x)+sin^2(x))

解

簡約

\frac{cos ^{2} ( x ) - sin ^{2} ( x )}{cos ^{2} ( x ) + sin ^{2} ( x )}

cos (2 x)

解答ステップ

\frac{cos ^{2} ( x ) - sin ^{2} ( x )}{cos ^{2} ( x ) + sin ^{2} ( x )}

簡素化

cos^{2} (x) - sin^{2} (x) : cos (2 x)

= \frac{cos ( 2 x )}{cos ^{2} ( x ) + sin ^{2} ( x )}

簡素化

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

= \frac{cos ( 2 x )}{1}

分数の規則を適用する:

\frac{a}{1} = a

= cos (2 x)