展开 (cos(x)+cot(x))^2

解答

展开

(cos (x) + cot (x))^{2}

cos^{2} (x) + 2 cos (x) cot (x) + cot^{2} (x)

求解步骤

(cos (x) + cot (x))^{2}

使用完全平方公式:

(a + b)^{2} = a^{2} + 2 ab + b^{2}

(cos (x) + cot (x))^{2} = cos^{2} (x) + 2 cos (x) cot (x) + cot^{2} (x)

= cos^{2} (x) + 2 cos (x) cot (x) + cot^{2} (x)

s im pl i f y x (x^{2} + 2 x)

e x p an d \frac{2 - tan ( x ) + x sec ^{2} ( x )}{( 2 - tan ( x ) ) ^{2}}

s im pl i f y 2 x^{2} - (1 + 23) x + 3

e x p an d \frac{3 ( x - 4 )}{5 ( x - 3 )}

e x p an d (2 + 1) (3 - 1)