Question

Simplify fully 6x2 +x–1 4x2 – 1

Answer 1

Answer:

​3x−1

Step-by-step explanation:

1 Split the second term in 6{x}^{2}+x-16x

​2

​​ +x−1 into two terms.

\frac{6{x}^{2}+3x-2x-1}{4{x}^{2}-1}

​4x

​2

​​ −1

​

​6x

​2

​​ +3x−2x−1

​​  

2 Factor out common terms in the first two terms, then in the last two terms.

\frac{3x(2x+1)-(2x+1)}{4{x}^{2}-1}

​4x

​2

​​ −1

​

​3x(2x+1)−(2x+1)

​​  

3 Factor out the common term 2x+12x+1.

\frac{(2x+1)(3x-1)}{4{x}^{2}-1}

​4x

​2

​​ −1

​

​(2x+1)(3x−1)

​​  

4 Rewrite 4{x}^{2}-14x

​2

​​ −1 in the form {a}^{2}-{b}^{2}a

​2

​​ −b

​2

​​ , where a=2xa=2x and b=1b=1.

\frac{(2x+1)(3x-1)}{{(2x)}^{2}-{1}^{2}}

​(2x)

​2

​​ −1

​2

​​  

​

​(2x+1)(3x−1)

​​  

5 Use Difference of Squares: {a}^{2}-{b}^{2}=(a+b)(a-b)a

​2

​​ −b

​2

​​ =(a+b)(a−b).

\frac{(2x+1)(3x-1)}{(2x+1)(2x-1)}

​(2x+1)(2x−1)

​

​(2x+1)(3x−1)

​​  

6 Cancel 2x+12x+1.

\frac{3x-1}{2x-1}

​2x−1

​

​3x−1

​​