Question

If f of x is equal to 5 x square minus 4x minus 1 then 0 of f of x - 1 is

Answer 1

f(x)= 5x^2 - 4x - 1 = 0 --> A)

f(x-1) = ?

Solution

Equation A can be written as,

5x^2 - 4x - 1 = 0 --> B)

now we need to put x = x-1 in equation B),

5(x-1)^2 - 4*(x-1) -1 =0

now applying (a-b)^2=a^2+b^2-2ab,

(x-1)^2=x^2+1-2x

5(x²-x+1)- 4x+ 4 -1=0

5x² -5x +5 -4x +4 -1=0

5x² -9x +8=0

so that,

f(x-1)=  5x² -9x +8=0