Toán Lớp 8: 20. 4x ²y ³ – 6x ³y ²
21. 5(x+y)+z(x+y)
22. 2x(3-x)-5(x-3)
23. 3x-x ² – 2(3-x)
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: 20. 4x ²y ³ – 6x ³y ²
21. 5(x+y)+z(x+y)
22. 2x(3-x)-5(x-3)
23. 3x-x ² – 2(3-x)
Comments ( 2 )
Giải đáp + Lời giải và giải thích chi tiết:
20, 4x^2y^3 – 6x^3y^2
=2x^2y^2(2y-3x)
21, 5(x+y)+z(x+y)
=(x+y)(5+z)
22, 2x(3-x)-5(x-3)
=2x(3-x)+5(3-x)
=(3-x)(2x+5)
23, 3x-x^2 – 2(3-x)
=(3x-x^2)-2(3-x)
=x(3-x)-2(3-x)
=(3-x)(x-2)
$\text{ @HV }$
20) 4x^2y^3 – 6x^3y^2
= 2x^2y^2. (2y – 3x)
_____________________________
21) 5. (x + y) + z. (x + y)
= (5 + z). (x + y)
______________________________
22) 2x. (3 – x) – 5. (x – 3)
= 2x. (3 – x) + 5. (3 – x)
= (2x + 5). (3 – x)
____________________________
23) 3x – x^2 – 2. (3 – x)
= x. (3 – x) – 2. (3 – x)
= (x – 2). (3 – x)