Giải phương trình

B

baochauhn1999

Câu a:
$(3x-1)(x^2+2)=(3x-1)(7x-10)$
$<=>(3x-1)(x^2-7x+12)=0$
$<=>(3x-1)(x-3)(x-4)=0$
$<=>x=3;4;\frac{1}{3}$
 
B

baochauhn1999

Câu b:
$(3x+2)(x^2-1)=(9x^2-4)(x+1)$
$<=>(3x+2)(x+1)(x-1)=(x+1)(3x+2)(3x-2)$
$<=>(3x+2)(x+1)(x-1-3x+2)=0$
$<=>(3x+2)(x+1)(1-2x)=0$
$<=>x=-1;\frac{1}{2};\frac{-2}{3}$
 
B

baochauhn1999

Câu c:
$(2x-5)^2-(x+2)^2=0$
$<=>(2x-5+x+2)(2x-5-x-2)=0$
$<=>(3x-3)(x-7)=0$
$<=>x=1;7$
 
B

baochauhn1999

Câu d:
$(3x^2+10x-8)^2=(5x^2-2x+10)^2$
$<=>(3x^2+10x-8)^2-(5x^2-2x+10)^2=0$
$<=>(3x^2+10x-8+5x^2-2x+10)(3x^2+10x-8-5x^2+2x-10)=0$
$<=>(8x^2+8x+2)(-2x^2+12x-18)=0$
$<=>2(2x+1)^2.2(x-3)^2=0$
$<=>x=3;\frac{-1}{2}$
 
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