Question

PLEASE HEP FAST: For f(x)=2x+1 and g(x)=x^2-7 fins (f o g)(x)
A.)2x^2-13
B.)2x^3+x^2-14x-7
C.)3x^2+7x-6
D.)2x^3-x^2-7x-7

Answer 1

$(2x + 1) \times ( {x }^{2} - 7) \\ = 2x( {x}^{2} ) + 2x( - 7) + 1( {x}^{2} ) + 1( - 7) \\ = 2 {x}^{3} + ( - 14x) + {x}^{2} + ( - 7) \\ = 2 {x}^{3} - 14x + {x}^{2} - 7 \\ = 2 {x}^{3} + {x}^{2} - 14x - 7$
The answer is B.

Answer 2

The correct answer is B.