log(x) 2 * log(0.25x) 2 = log(16x) 2
одз
x>0
x<>1
x<>4
x<>1/16
log(a) b = 1/log(b) a
1/log(2) x * 1/log(2) 0.25x = 1/log(2) 16x
log(2) x * log(2) 0.25x = log(2) 16x
log(2) x * ( log(2) x + log(2) 1/4) = log(2) x + log(2) 16
log²(2) x - 2*log(2) x = log(2) x + 4
log²(2) x - 3*log(2) x - 4 = 0
D=9+16=25
log(2) x = (3+-5)/2=-1 4
x=1/2
x=16