Question

Dau coroana si 50 de puncte.​

Answer 1

(2^x)^2 = 2^2

2x= 2

x= 1

notezi pe 2^x = t

t^2 -5t+4=0

delta = 25-16= 9

t1= (5+3)/2 = 8/2 = 4

t2 = (5-3)/2 = 2/2 = 1

din t1 = 2^x, 2^x= 4, 2^x = 2^2, x=2

t2 = 2^x, 2^x = 1, 2^x = 2^0, x=0

S={0,2}

notezi log2 (x) = t

t^2 -3t+2 <0

delta = 9-8 =1

t1 = (3+1)/2 = 4/2 = 2

t2 = (3-1)/2 = 2/2= 1

din t1 = log2 (x), log2 (x) = 2, x= 2^2 = 4

din t2 = log2 (x), log2 (x) = 1, x=2^1 = 2

S={2,4}