Algebra?

Hello xrabia!

Solve 2^2x-5(2^x)+4=0

2^2x - 5 * 2^x + 4=0         [2^x = u

u² - 5u + 4 = 0

u_1;2 = 2.5 ±√(6.25 - 4)

u_1;2 = 2,5 ± 1.5

u₁ = 4

2^x1 = 4

2^x1 = 2²

x₁ = 2

u₂ = 1

2^x2 = 1

2^x2 = 2⁰

x₂ = 0

Greeting asinus :- )  !