Question

Is this equation an identity? (2x+1)^2-(x+1)^2=3(x+1)^2-1

Answer 1

Answer:

See below, please

Step-by-step explanation:

Left side

${(2x + 1)}^{2} - {(x + 1)}^{2}$

$= (4 {x}^{2} + 4x + 1) - ( {x}^{2} + 2x + 1)$

$= (4 {x}^{2} - {x}^{2} ) + (4x - 2x) + (1 -1 )$

$= 3 {x}^{2} + 2x$

Right side

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

$= 3 \times ( {x}^{2} + 2x + 1) - 1$

$= 3 {x}^{2} + 6x + 3 - 1$

$= 3 {x}^{2} + 6x + 2$

After compared with both sides, we can make a conclusion that

This equation isn't an identity.