4^x-5*2^x+4=0 решение уравнений

Question

4^x-5*2^x+4=0 решение уравнений

Answer 1

2^2x -5*2^x+4=0
2^x=a
a²-5a+4=0
a1+a2=5 U a1*a2=4
a1=1⇒2^x=1⇒x=0
a2=4⇒2^x=4⇒x=2
Ответ x=0;x=2

Answer 2

4^x  - 5*2^x + 4 = 0 
2^x = t

t^2  - 5t + 4 = 0 
D = 25 - 16 = 9 
t1 = (5 + 3)/2 = 8/2 = 4;
t2 = (5 - 3)/2 = 2/2 = 1;

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

2^x = 1
2^x = 2^0
x = 0