Toán Lớp 8: a)-8x^2+23x+3 b)8x^2-23x-3 c)10x^2-11x-6 d)-10x^2+11x+6 e)10x^2-4x-6 g)-10x^2+4x+6 đ)10x^2+7x-6 i)-10x^2-7x+6 h)10x^2+17x-6

Question

Toán Lớp 8:  a)-8x^2+23x+3 b)8x^2-23x-3 c)10x^2-11x-6 d)-10x^2+11x+6 e)10x^2-4x-6 g)-10x^2+4x+6 đ)10x^2+7x-6 i)-10x^2-7x+6 h)10x^2+17x-6

hienthucthu97 · Answer

Giải đáp:   a/  -8x&sup2;+23x+3     =-(8x&sup2;-24x)-(x-3)    =-8x(x-3)-(x-3)   =-(x-3)(8x+1)      b/ 8x&sup2;-23x-3     =(8x&sup2;-24x)+(x-3)     =8x(x-3)+(x-3)     = (x-3)(8x+1)      c/ 10x&sup2;-11x-6     =(10x&sup2;-15x)+(4x-6)     =5x(2x-3)+2(2x-3)     =(2x-3)(5x+2)        d/-10x&sup2;+11x+6     =-(10x&sup2;-15x)-(4x-6)     =-  5x(2x-3)-2(2x-3)     =-(2x-3)(5x+2)        e/10x&sup2;-4x-6     =(10x&sup2;-10x)+(6x-6)     =10x(x-1)+6(x-1)     =(x-1)(10x+6)        g/ -10x&sup2;+4x+6     =-(10x&sup2;-10x)-(6x-6)     =-10x(x-1)-6(x-1)     =-(x-1)(10x+6)        đ/ 10x&sup2;+7x-6     =(10x&sup2;-5x)+(12x-6)     =5x(2x-1)+6(2x-1)     =(2x-1)(5x+6)        i/-10x&sup2;-7x+6    =(-10x&sup2;+5x)+(-12x+6)   =-5x(2x-1)-6(2x-1)   =-(2x-1)(5x+6)      h/  10x&sup2;+17x-6     =(10x&sup2;+20x)-(3x+6)     =10x(x+2)-3(x+2)     =(x+2)(10x-3)

thanhmaianh · Answer

$a.-8x^{2}+23x+3$   $=-8x^{2}+24x-x+3$   $=-8x^{}(x-3)-(x-3)$   $=(x^{}-3)(-8x-1)$   $b.8x^{2}-23x-3$   $=8x^{2}-24x+x-3$   $=8x^{}(x-3)+(x-3)$   $=(8x^{}+1)(x-3)$   $c.10x^{2}-11x-6$   $=10x^{2}-15x+4x-6$   $=5x^{}(2x-3)+2(2x-3)$    $=(2x^{}-3)(5x+2)$   $d.-10x^{2}+11x+6$   $=-(10x^{2}+11x+6)$   $=-(5x^{}+2)(2x-3)$ (l&agrave;m giống c&acirc;u c)   $=(5x^{}+2)(3-2x)$   $e.10x^{2}-4x-6$   $=10x^{2}-10x+6x-6$   $=10x^{}(x-1)+6(x-1)$   $=2(x^{}-1)(5x+3)$   $g.-10x^{2}+4x+6$   $=-(10x^{2}-4x-6)$   $=-2(x^{}-1)(5x+3)$ (l&agrave;m giống c&acirc;u e)   $=2(1-x^{})(5x+3)$   $đ.10x^{2}+7x-6$   $=10x^{2}-5x+12x-6$   $=5x^{}(2x-1)+6(2x-1)$   $=(2x^{}-1)(5x+6)$   $i.-10x^{2}-7x+6$   $=-(10x^{2}+7x-6)$   $=-(2x^{}-1)(5x+6)$ (l&agrave;m giồng c&acirc;u đ)   $=(1-2x^{})(5x+6)$   $h.10x^{2}+17x-6$   $=10x^{2}+20x-3x-6$   $=10x^{}(x+2)-3(x+2)$   $=(x^{}+2)(10x-3)$   Ch&uacute;c bạn học tốt !!!!!!