展开 cos(x)(2sin(x)-1)

解答

展开

cos (x) (2 sin (x) - 1)

sin (2 x) - cos (x)

求解步骤

cos (x) (2 sin (x) - 1)

使用分配律:

a (b - c) = ab - a c

cos (x) (2 sin (x) - 1) = cos (x) \cdot 2 sin (x) - cos (x) \cdot 1

= cos (x) \cdot 2 sin (x) - cos (x) \cdot 1

化简

cos (x) \cdot 2 sin (x) - cos (x) \cdot 1 : sin (2 x) - cos (x)

= sin (2 x) - cos (x)

s im pl i f y ((V - \frac{k \cdot c}{t \cdot s + 1}) A) F

e x p an d x^{\frac{4}{5}} (8 x - 32)^{2}

e x p an d \frac{x - 1}{( x + 1 ) ( x - 3 )}

e x p an d (0, 4) y (0, - 4)

e x p an d 25 (e^{- t} - e^{- 2 t})