a)\(P=\left(5x-1\right)+2\left(1-5x\right)\left(4+5x\right)+\left(5x+4\right)\)

   \(P=5x-1+5x+4+\left(2-10x\right)\left(4+5x\right)\)

   \(P=10x+3+8+10x-40x-50x^2\)

    \(P=-20x+11-50x^2\)

b)\(Q=\left(x-y\right)^3+\left(y+x\right)^3+\left(y-x\right)^3-3xy\left(x+y\right)\)

   \(Q=x^3-3x^2y+3xy^2-y^3+y^3+3y^2x+3yx^2+x^3+y^3-3y^2x+3yx^2-x^3-3x^2y+3xy^2\)

   \(Q=x^3+y^3\)

a)

P=(5x−1)+2(1−5x)(4+5x)+(5x+4)²
P=(5x−1)²+2(1−5x)(4+5x)+(5x+4)²−(5x−1)²
P=(5x−1+5x+4)²−(5x−1)²
P=(5x−1+5x+4−5x+1)(5x−1+5x+4+5x−1

b)

Q= (x-y)^3 + (x+y)^3 + (y-x)^3 - [3xy(x+y)] 

(x-y)^3 = x^3 - 3x^2y + 3xy^2 - y^3 

(x+y)^3 = x^3 + 3x^2y + 3xy^2 + y^3 

(y-x)^3 = y^3 - 3xy^2 + 3x^2y - x^3 

Q= (2x^3 + 6xy^2) + (y^3 - 3xy^2 + 3x^2y - x^3) - [3xy(x+y)] 
= (x^3 + 3xy^2 + 3x^2y + y^3) - 3x^2y - 3xy^2 
Q= x^3 + y^3

phần p thiều bk ơi

q=x^3 - y^3 + y^3 + x^3 + y^3 - x^3 - 3x^2y + 3xy^2

rồi thu gọn

a đề sai

a ) phải là\(\left(5x-1\right)^2+2\left(1-5x\right)\left(4+5x\right)+\left(5x+4\right)^2\)

a) P= (5x-1)+2(1-5x)(4+5x)+(5x+4)²

P = (5x-1)² + 2(1 - 5x)(4 + 5x)+ (5x + 4)² - (5x - 1)²

P = (5x - 1 + 5x + 4)² - (5x - 1)²

P = (5x - 1 + 5x + 4 - 5x + 1) (5x - 1 + 5x + 4 + 5x - 1)

b) làm tương tự nhé!! kết quả: Q = x³ + y³

t i c k nha!! 5364574674675678568585785789769647568585

a.

Bn tham khảo nhé

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