Question

4^x-1 -5.2^x +16 =???
Tolong bantu caranya yaa..

Answer 1

Langsung ke cara...

2^2x-2 - 5.2^x + 16 = 0 2^x = a
1/4 a^2 - 5a + 16 =0
semua ruas dikalikan 4

a^2 - 20a +64 = 0
(a - 4) (a - 16) = 0
a = 4, a = 16

2^x = 4 2^x = 16
x = 2 x = 4

sorry ya, klo salah....