Đáp án+Giải thích các bước giải:
`a) 5x(3x-1)-3(5x²+5)=0`
`⇔15x²-5x-15x²-15=0`
`⇔-5x-15=0`
`⇔-5x=15`
`⇔x=-3`
Vậy `S={-3}`
`b) 2x(6x+1)-(4x-3)(3x-2)=0`
`⇔12x²+2x-(12x²-8x-9x+6)=0`
`⇔12x²+2x-12x²+8x+9x-6=0`
`⇔19x-6=0`
`⇔19x=6`
`⇔x=6/19`
Vậy `S={6/19}`
`c) (3x-2)²=(3x-1)(3x+1)`
`⇔9x²-12x+4=9x²-1`
`⇔9x²-12x+4-(9x²-1)=0`
`⇔9x²-12x+4-9x²+1=0`
`⇔-12x+5=0`
`⇔-12x=-5`
`⇔x=5/12`
Vậy `S={5/12}`
`d) (2x+3)²=4(x²+6)`
`⇔4x²+12x+9=4x²+24`
`⇔4x²+12x+9-(4x²+24)=0`
`⇔4x²+12x+9-4x²-24=0`
`⇔12x-15=0`
`⇔12x=15`
`⇔x=5/4`
Vậy `S={5/4}`
`e) (4x+1)²=15(x²-1)`
`⇔16x²+8x+1=15x²-15`
`⇔16x²+8x+1-(15x²-15)=0`
`⇔16x²+8x+1-15x²+15=0`
`⇔x²+8x+16=0`
`⇔(x+4)²=0`
`⇔x+4=0`
`⇔x=-4`
Vậy `S={-4}`
Chúc bn hc tốt🥰
$\text{#LinhSad}$
