展开-4/3 cos(2)(x-pi/2)

解答

展开

- \frac{4}{3} cos (2) (x - \frac{π}{2})

- \frac{4 cos ( 2 ) x}{3} + \frac{2 π cos ( 2 )}{3}

求解步骤

- \frac{4}{3} cos (2) (x - \frac{π}{2})

使用分配律:

a (b - c) = ab - a c

a = - \frac{4}{3} cos (2), b = x, c = \frac{π}{2}

= - \frac{4}{3} cos (2) x - (- \frac{4}{3} cos (2)) \frac{π}{2}

使用加减运算法则

- (- a) = a

= - \frac{4}{3} cos (2) x + \frac{4}{3} \cdot \frac{π}{2} cos (2)

化简

- \frac{4}{3} cos (2) x + \frac{4}{3} \cdot \frac{π}{2} cos (2) : - \frac{4 cos ( 2 ) x}{3} + \frac{2 π cos ( 2 )}{3}

= - \frac{4 cos ( 2 ) x}{3} + \frac{2 π cos ( 2 )}{3}

\frac{d}{d x} ((z) (x^{2} + y^{2} - z^{2}))

e x p an d \frac{x}{( x - a ) ( x - b )}

s im pl i f y (x - 3) \times (x + 3)

e x p an d (m^{2} - 2 mn - 8 n^{2}) (m^{3} - 3 m^{2} n + 2, m n^{2})

e x p an d \frac{4 ( x + 3 ) ( x + 1 )}{( x + 5 ) ( x - 5 )}