Решить уравнение . 1) 2^х-1+2^х-2+2^х-3=448 2) 4^х-3×2=40

1) 2^(x-1) +2^(x-2) +2^(x-3) = 448
2^(x-3) (2^2 + 2^1 +1) = 448
2^(x-3)·7 = 448 | :7
2^(x-3) = 64
2^(x-3) = 2^6
x-3 = 6
x = 9
2)4^(x-2) =20
(x-2)lg4 = lg20
x-2 = lg20/lg4
x = lg20/lg4 +2