Question

Evaluate 2x^2 – 1 when x=3

Answer 1

17 .

Step by step explanation:

Substitute the value of x into the equation and square it.

the equation then becomes 2(3)^2- 1

but 3^2 =3×3 =9

So the equation is changed to 2(9)-1 after the simplification

given you 18-1

=17

Answer 2

17

Explanation:

Given: 2x² – 1

when x=3

2(3)² – 1

= 2(9) -1

= 18 - 1

= 17