Đáp án:
bên dưới
Giải thích các bước giải:
1) 5ax + 5ay + x + y
= 5a(x + y) + 1(x + y)
= (x + y)(5a + 1)
2) 2xy - x + 2y^2 - y
= (2xy + 2y^2) - (x + y)
= 2y(x + y) - 1(x + y)
= (x + y)(2y - 1)
3) ax + bx - ay - by
= (ax - ay) + (bx - by)
= a(x - y) + b(x - y)
= (x - y)(a + b)
4) x^2 + xy + ax + ay
= x(x + y) + a(x + y)
= (x + y)(x + a)
5) ac + bc + a + b = c(a + b) + 1(a + b)
= (a + b)(c + 1)
Hoặc ac + bc + a + b = ac + a + bc + b
= a(c + 1) + b(c + 1)
= (c + 1)(a + b)
6) 3a - 3b + ax - bx
= 3(a - b) + x(a - b)
= (a - b)(3 + x)
7) x^3 + 9 + 3x^2 + 3x
= x^3 + 3x + 3x^2 + 9
= x(x^2 + 3) + 3(x^2 + 3)
= (x^2 + 3)(x + 3)
Hoặc x^3 + 9 + 3x^2 + 3x = x^3 + 3x^2 + 3x + 9
= x^2(x + 3) + 3(x + 3)
= (x + 3)(x^2 + 3)
8) 10ay - 5by + 2ax - bx
= (10ay + 2ax ) - (5by + bx)
= 2a(5y + x) - b(5y + x)
= (5y + x)(2a - b)
9) 5a^2 - 7a - 5ax+ 7x
= (5a^2 - 5ax) - (7a - 7x)
= 5a(a - x) - 7(a - x)
= (a - x)(5a - 7)
10) x^2 - 3y - 3xy + x
= (x^2 + x) - (3y + 3xy)
= x(x + 1) - 3y(x + 1)
= (x + 1)(x - 3y)
11) xz + 7x - 2yz - 14y
= x(z + 7) - (2yz + 14y)
= x(z + 7) - 2y(z + 7)
= (z + 7)(x - 2y)
12)12xm+9my-8xz-6xy
hình như câu này có vấn đề
13) 2x^2 - xz - 8xy + 4yz
= (2x^2 - 8xy) - (xz - 4yz)
= 2x(x - 4y) - z(x - 4y)
= (x - 4y)(2x - z)
14) 3ax - 4by - 4ay + 3bx
= (3ax + 3bx) - (4by + 4ay)
= 3x(a + b) - 4y(a + b)
= (a + b)(3x - 4y)
15) 30ax - 34bx - 15a + 17b
= (30ax - 15a) - (34bx - 17b)
= 15a(1 - 2x) - 17b(1 - 2x)
= (1 - 2x)(15a - 17b)
