common.or
auth.dont_have_account auth.register
Solve the following mathematical problems:
Factorize: x3-21x+20
Given, x3-21x+20 let, f(x)=x3-21x+20 Here, if x=1, then f(x) = 0 ∴ (x-1) will be the factor of f(x) ∴x3-21x+2 =x3-x2+x2-x-20x+20 =x2(x-1)+x(x-1)-20(x-1) =(x-1)(x2+x-20) =(x-1)(x2+5x-4x-20) =(x-1){(x(x+5)-4(x+5)} =(x-1) (x+5) (x-4) (answer)
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