Toán Lớp 8: a,x^2-4x+3 b,x^2+4x-12
c,2x^2-3x-2 d, 2x^3+x-2x^2-1
e, x^4+2x^2-8 f, x^2-2xy-3y^2
mọi người giúp mình nhé
Leave a reply
Register Now
Login
Lost Password
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Toán Lớp 8: a,x^2-4x+3 b,x^2+4x-12
c,2x^2-3x-2 d, 2x^3+x-2x^2-1
e, x^4+2x^2-8 f, x^2-2xy-3y^2
mọi người giúp mình nhé
Comments ( 2 )
CHÚC BẠN HỌC TỐT!!!!
a) $x^{2}$ – $4x^{}$ + $3^{}$
= $x^{2}$ – $x^{}$ – $3x^{}$ + $3^{}$
= $x^{}$.$(x-1)^{}$ – $3^{}$.$(x-1)^{}$
= $(x-1)^{}$.$(x-3)^{}$
b) x^2+4x-12
= x^2 + 6x-2x-12
= x.(x+6)-2.(x+6)
= (x-2)(x+6)
c) 2x^2-3x-2
= 2x^2-4x+x-2
= 2x.(x-2)+(x-2)
d) 2x^3+x-2x^2-1
= x.(2x^2+1)-(2x^2+1)
= (2x^2+1)(x-1)
e) x^4+2x^2-8
= x^4-2x^2+4x^2-8
=x.(x^2-2)+4.(x^2-2)
= (x^2-2).(x+4)
f) x^2-2xy-3y^2
= $x^{2}$ – $2xy^{}$ + $y^{2}$ – $y^{2}$ – $3y^{2}$
= $(x-y)^{2}$ – $4y^{2}$
= (x-3y).(x+y)
Xin hay nhất ạ -.-