Question

x² - 1     

  1 - x²   

   2 - x²

   3 - x²   

  x² - 9   

x² - 4   

  x² - 16 

    x² - 25

Answer 1

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

b: \(1-x^2=\left(1-x\right)\left(1+x\right)\)

b: \(2-x^2=\left(\sqrt{2}-x\right)\left(\sqrt{2}+x\right)\)

c: \(3-x^2=\left(\sqrt{3}-x\right)\left(\sqrt{3}+x\right)\)

d: \(x^2-9=\left(x-3\right)\left(x+3\right)\)

e: \(x^2-4=\left(x-2\right)\left(x+2\right)\)

f: \(x^2-16=\left(x-4\right)\left(x+4\right)\)

Answer 2

Ta có: `x^2- y^2 =(x-y)(x+y)`

`a, (x^2-1) = (x+y)(x-y)`

`b, 1-x^2 = (1-x)(1+x)`

`c, 2-x^2 = (sqrt 2 - x)(sqrt 2 + x)`

`d, 3 - x^2 = (sqrt 3 - x)(sqrt 3 + x)`

`e, x^2 - 9 = (x - 3)(x+3)`

`f, x^2-4 = (x-2)(x+2)`

`g, x^2-16 = (x-4)(x+4)`

`h, x^2-25=(x-5)(x+5)`

Answer 3

\(=\left(x-1\right)\left(x+1\right)\\ =\left(1-x\right)\left(1+x\right)\\ =\left(\sqrt{2}-x\right)\left(\sqrt{2}+x\right)\\ =\left(\sqrt{3}+x\right)\left(\sqrt{3}-x\right)\\ =\left(x-3\right)\left(x+3\right)\\ =\left(x+2\right)\left(x-2\right)\\ =\left(x-4\right)\left(x+4\right)\)

Answer 4

\(x^2-1=\left(x-1\right)\left(x+1\right)\\ 1-x^2=\left(1-x\right)\left(1+x\right)\\ 2-x^2=\left(\sqrt{2}-x\right)\left(\sqrt{2}+x\right)\\ 3-x^2=\left(\sqrt{3}-x\right)\left(\sqrt{3}+x\right)\\ x^2-9=\left(x-3\right)\left(x+3\right)\\ x^2-4=\left(x-2\right)\left(x+2\right)\\ x^2-16=\left(x-4\right)\left(x+4\right)\\ x^2-25=\left(x-5\right)\left(x+5\right)\)