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

\(=2a^2+2b^2+2c^2+2ab+2ac+2bc-2ab-2bc+2ac-4b^2\)

\(=2a^2-2b^2+2c^2+4ac\)

\(=2\left[\left(a^2+2ac+c^2\right)-b^2\right]=2\left[\left(a+c\right)^2-b^2\right]\)

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

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

\(=a^2+b^2+c^2+2ab+2bc+2ca+a^2+b^2+c^2-2ab-2bc+2ca-4b^2\)

\(=2a^2-2b^2+2c^2+4ca\)

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

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

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

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

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

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

\(=\left[a^2-\left(b^2-2bc+c^2\right)\right].\left[\left(b^2+2bc+c^2\right)-a^2\right]\)

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

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

\(\left(a^2+b^2-5\right)^2-4\left(ab+2\right)^2\)

\(=\left(a^2+b^2-5-2ab-4\right)\left(a^2+b^2-5+2ab+4\right)\)

\(=\left[\left(a-b\right)^2-3^2\right].\left[\left(a+b\right)^2-1\right]\)

\(=\left(a-b-3\right)\left(a-b+3\right)\left(a+b-1\right)\left(a+b+1\right)\)

Tham khảo nhé~

Bài 1.

\(a\Big) 9(4x+3)^2=16(3x-5)^2\\\Leftrightarrow 9[(4x)^2+2\cdot 4x\cdot3+3^2]=16[(3x)^2-2\cdot3x\cdot5+5^2]\\\Leftrightarrow9(16x^2+24x+9)=16(9x^2-30x+25)\\\Leftrightarrow 144x^2+216x+81=144x^2-480x+400\\\Leftrightarrow (144x^2-144x^2)+(216x+480x)=400-81\\\Leftrightarrow 696x=319\\\Leftrightarrow x=\dfrac{11}{24}\\Vậy:x=\dfrac{11}{24}\\---\)

\(b\Big)(x-3)^2=4x^2-20x+25\\\Leftrightarrow(x-3)^2=(2x)^2-2\cdot2x\cdot5+5^2\\\Leftrightarrow(x-3)^2=(2x-5)^2\\\Leftrightarrow (x-3)^2-(2x-5)^2=0\\\Leftrightarrow (x-3-2x+5)(x-3+2x-5)=0\\\Leftrightarrow (-x+2)(3x-8)=0\\\Leftrightarrow \left[\begin{array}{} -x+2=0\\ 3x-8=0 \end{array} \right.\\\Leftrightarrow \left[\begin{array}{} -x=-2\\ 3x=8 \end{array} \right.\\\Leftrightarrow \left[\begin{array}{} x=2\\ x=\dfrac{8}{3} \end{array} \right.\\Vậy:...\)

a) \(\left(6x-1\right)^2-\left(3x+2\right)^2\)

\(=\left(6x-1+3x+2\right)\left(6x-1-3x-2\right)\)

\(=\left(9x+1\right)\left(3x-3\right)\)

\(=3\left(9x+1\right)\left(x-1\right)\)

b) \(9\left(2x+3\right)^2-4\left(x+1\right)^2\)

\(=\left(6x+9\right)^2-\left(2x+2\right)^2\)

\(=\left(6x+9+2x+2\right)\left(6x+9-2x-2\right)\)

\(=\left(8x+11\right)\left(4x+7\right)\)

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

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

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

\(=-\left[\left(b+c\right)^2-a^2\right]\left(b^2-2bc+c^2-a^2\right)\)

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

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

d) \(\left(a^2+b^2-5\right)^2-4\left(ab+2\right)^2\)

\(=\left(a^2+b^2-5\right)^2-\left(2ab+4\right)^2\)

\(=\left(a^2+b^2-5+2ab+4\right)\left(a^2+b^2-5-2ab-4\right)\)

\(=\left[\left(a+b\right)^2-1\right]\left[\left(a-b\right)^2-3^2\right]\)

\(=\left(a+b+1\right)\left(a+b-1\right)\left(a-b-3\right)\left(a-b+3\right)\)

Bạn Trợ sai m* nó r

bạn ra 2 câu 1 bài chứ nhìu thế ko ai giải đâu

a = x( x³ - 4x² + 8x - 16)

c, (ab - xy)² - (bx - ay)² 

dựa theo hằng đẳng thức a² - b² = ( a + b)(a - b)

=> = [ ( ab - xy) + ( bx - ay)] . [ ( ab - xy) - ( bx - ay) ]

tương tự làm câu d theo câu c

Mình không biết

ko bt thì  ko nói nha mình đang cần gấp lém xin đừng trêu

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

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

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

\(=\left(b-c\right)\left(ab^2+ac^2-bc^2-ba^2\right)-\left(a-b\right)\left(bc^2+ba^2-ca^2-cb^2\right)\)

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

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

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

tk mình đi mình giải cho 

\(=a^2b-a^2c+b^2c-b^2a+c^2a-c^2b\)

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

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

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

\(=\left(a-b\right)\left[a\left(b-c\right)-c\left(b-c\right)\right]\)

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