Question

решите уравнения
б)(1/64)^x=√1/2
в)2^x2-8x+19=16
г)lg x-4/2-x=0
Срочно нужна помощь

Answer 1

б)$2^{-6x} = 2^{-1/2}$
-6x=-1/2
x=1/12
в)$2^{x^2-8x+19} =2^4$
x²-8x+19=4
x²-8x+15=0
x1+x2=8 U x1*x2=15
x1=3 U x2=5
г)(x-4)/(2-x)>0
x=4 U x=2
x∈(2;4)
(x-4)/(2-x)=1
x-4=2-x
x+x=2+4
2x=6
x=3

Answer 2

$b) (frac{1}{64})^x=sqrt{frac{1}{2}}\ ((frac{1}{sqrt2})^{12})^x=frac{1}{sqrt2}\ (frac{1}{sqrt2})^{12x}=frac{1}{sqrt2}\ 12x=1\ x=frac{1}{12}\ v) 2^{x^2-8x+19}=16\ 2^{x^2-8x+19}=2^4\ x^2-8x+19=4\ x^2-8x+15=0\ |x=3\ |x=5\ g) frac{lgx-4}{2-x}=0\ x>0; xneq2\ lgx-4=0\ lgx=4\ lgx=lg10^4\ x=10^4=10000$