Đáp án:
Giải thích các bước giải:
1, √3x -2 = 4
⇔√(3x -2)²=4²
⇔3x-2=16
⇔3x=18
⇔x=6
2,√4x²-4x+1 -11=5
⇔√(2x-1)²=16
⇔2x-1=16
⇔2x=17
⇔x=17/2
3,√x² -10x +25=4
⇔√(x-5)²=4
⇔x-5=4
⇔x=9
4,√x²-6x+9=2x+1
⇔√(x-3)²=2x+1
⇔x-3=2x+1
⇔-x=4
⇔x=-4
5, √25x² -30x +9=x+7
⇔√(5x-3)²=x+7
⇔5x-3=x+7
⇔4x=10
⇔x=5/2
6,√16x +32 +1/3(√9x+18) - 4√x+2/4=16
⇔4√x+2 +√ x+2-2√x+2=16
⇔3√x+2=16
⇔√x+2=16/3
⇔√(x+2)²=(16/3)²
⇔x+2=256/9
⇔x=238/9
