5 логарифмических уравнений

1
x^2-14x=32
x^2-14x-32=0
x1=16
x2=-2
б) х=-2

log(8)x=t
6t^2-5t+1=0
D=25-24=1
t1=(5+1)/12=1/2
t2=(5-1)/12=1/3
log(8)x=1/2
x1=2√2
log(8)x=1/3
x2=2
б) х=2

log(2)2+log(2)(9x^2+5)=log(2^1/2)(8x^4+14)^(1/2)
log(2)(2*(9x^2+5)=2:1/2log(2)(8x^4+14)
18x^2+10=8x^4+14
8x^4-18x^2+4=0
4x^4-9x^2+2=0
x^2=t
4t^2-9t+2=0
D=81-32=49
t1=(9+7)/8=2
t2=(9-7)/8=1/4
x^2=1/4
x1=-1/2
x2=1/2
x^2=2
x3=-√2
x4=√2
б) х1=-1/2 x2=1/2
вроде, так