Question

Bài 1: Viết các biểu thức sau dưới dạng tích:

a) y^2 - 24y+144

b)y^2 - (7x)^2

c)y^2 + 14y + 49

d)25x^2 - 64y^2

Giúp mình với ạ! sos

Answer 1

\(a,=\left(y-11\right)^2\\ b,=\left(y-7x\right)\left(y+7x\right)\\ c,=\left(y+7\right)^2\\ d,=\left(5x-8y\right)\left(5x+8y\right)\)

Answer 2

`a)y^2-24y+144=y^2-2.y.12+12^2=(y-12)^2`

`b)y^2-(7x)^2=(y-7x)(y+7x)`

`c)y^2+14y+49=y^2+2.y.7+7^2=(y+7)^2`

`d)25x^2-64y^2=(5x)^2-(8y)^2=(5x-8y)(5x+8y)`

Answer 3

a) \(\left(y-12\right)^2\)

b) \(\left(y-7x\right)\left(y+7x\right)\)

c) \(\left(y+7\right)^2\)

d) \(\left(5x-8y\right)\left(5x+8y\right)\)

Answer 4

\(y^2-24y+144=y^2-2.y.12+12^2=\left(y-12\right)^2\\ y^2-\left(7x\right)^2=\left(y-7x\right)\left(y+7x\right)\\ y^2+14y+49=y^2+2.y.7+7^2=\left(y+7\right)^2\\ 25x^2-64y^2=\left(5x\right)^2-\left(8y\right)^2=\left(5x-8y\right)\left(5x+8y\right)\)