mik xin ko lm câu c ạ
`a, (-2/3)^x =4/9`
`=> (-2/3)^x = (-2/3)^2`
`=> x = 2`
`b, (x-1)^2 = 1/25`
`=> (x-1)^2 = (1/5)^2`
`+,x-1 = 1/5`
`=> x = 6/5`
`+,x-1 = -1/5`
`=> x=4/5`
Vậy `x =` `6/5` hoặc `4/5`
`d, 32/2^x = 4`
`=> 32/2^x = 32/8`
`=> 2^x = 8`
`=> 2^x = 2^3`
`=> x = 3`
`e, 5^x + 5^(x+1) = 150`
`=> 5^x + 5^x * 5 = 150`
`=> 5^x*(1+5) = 150`
`=> 5^x*6 = 150`
`=> 5^x = 150:6`
`=> 5^x = 25`
`=>5^ x = 5^2`
`=> x=2`