a2 – b2 – 4a + 4

= a2 – 4a + 4 – b2

= (a – 2)2 – b2

= (a – 2 + b)(a – 2 – b)

= (a + b – 2)(a – b – 2)

thêm bớt 4(x-a)^2 . a^2 là được

làm ra rứa ná

nói rõ ra đc ko bạn

\(4a^4b-24a^3b^2+36a^2b^3\)

\(=4a^2b\left(a^2-6ab+9b^2\right)\)

\(=4a^2b\left[a^2-2.a.3b+3b^2\right]\)

\(=4a^2b\left(a-3b\right)^2\)

\(4a^4b-24a^3b^2+36a^2b^3\)

\(=4a^2b\left(a^2-6ab+9b^2\right)\)

\(=4a^2b\left[a^2-2\cdot a\cdot3b+\left(3b\right)^2\right]\)

\(=4a^2b\left(a-3b\right)^2\)

   4a⁴b - 24a³b² + 36a²b³

= 4a²b * ( a² - 6ab + 9b² )

= 4a²b * ( a - 3b ) ²

4a²b² + 36a²b³ + 6ab⁴

= 2ab²(2a + 18ab + 3b²)

4a²b³ - 6a³b²

= 2a²b²(2b - 3a)

\(4a^3-3a+1\)

\(=\left(4a^3-4a\right)+\left(a+1\right)\)

\(=4a\left(a^2-1\right)+\left(a+1\right)\)

\(=4a\left(a-1\right)\left(a+1\right)+\left(a+1\right)\)

\(=\left(a+1\right)\left(4a^2-4a+1\right)\)

\(=\left(a+1\right)\left(2a-1\right)^2\)

\(M=\left(a^2+b^2-c^2\right)^2-4a^2b^2\)

\(M=\left(a^2+b^2-c^2\right)^2-\left(2ab\right)^2\)

\(M=\left(a^2+b^2-c^2-2ab\right)\left(a^2+b^2-c^2+2ab\right)\)

\(M=\left(\left(a^2-2ab+b^2\right)-c^2\right)\left(\left(a^2+2ab+b^2\right)-c^2\right)\)

\(M=\left(\left(a-b\right)^2-c^2\right)\left(\left(a+b\right)^2-c^2\right)\)

\(M=\left(a-b-c\right)\left(a-b+c\right)\left(a+b-c\right)\left(a+b+c\right)\)

\(a^3+4a^2-7a-10\)

\(=\left(a^3+5a^2\right)-\left(a^2+5a\right)-\left(2a+10\right)\)

\(=a^2\left(a+5\right)-a\left(a+5\right)-2\left(a+5\right)\)

\(=\left(a^2-a-2\right)\left(a+5\right)\)

\(=\left(a^2-2a+a-2\right)\left(a+5\right)\)

\(=\left[a\left(a-2\right)+\left(a-2\right)\right]\left(a+5\right)\)

\(=\left(a+1\right)\left(a-2\right)\left(a+5\right)\)

b) 4 – x2 – 2xy – y2 = 4 – (x2 + 2xy + y2) = 4 – (x + y)2

= (2 + x + y)(2 – x – y)