化简 (3i)(5-4i)

解答

化简

(3 i) (5 - 4 i)

12 + 15 i

求解步骤

(3 i) (5 - 4 i)

使用分配律:

a (b - c) = ab - a c

(3 i) (5 - 4 i) = 3 i 5 - 3 i 4 i

= 3 i 5 - 3 i 4 i

3 i 5 = 15 i

- 3 i 4 i = 12

= 15 i + 12

Rewrite in standard complex form:

12 + 15 i

= 12 + 15 i

s im pl i f y e^{4 i}

e x p an d (y - 2)^{11}

s im pl i f y (x + 4 + 10) (x + 4 - 10)

f a c t or 4 x y - 11 x a + 15 x y a

s im pl i f y f^{5} g