Question

What is the standard form of `f(x)=(x+1)(x+3)+(-2x-1)^2`?

Answer 1

The standard form of this equation is :
`f(x) = 5x^2 + 8x + 4`

Explanation:

The standard form of an equation should look like :
`f(x) = ax^2 + bx + c`

First, you have to develop the right member : `(x+1)(x+3)+(-2x-1)^2`

`[ (x*x)+(x*3)+(1*x)+(1*3)] + [ (-2x)^2 - 2*(-2x*1) + 1^2]`
Then, we can simplified it :
`[ x^2+3x+x+3] + [ 4x^2 + 4x + 1]`
`x^2+4x+3 + 4x^2 + 4x + 1`
`5x^2+8x+4`

So, `f(x) = 5x^2 + 8x + 4`