Question

What must be added to (a³−4a²−6a−5) to obtain (4a³+2a²+7a−4)?

a) 9a³+6a²+13a−1
b) 9a³+6a²−13a+1
c) 9a³−6a²+13a+1
d) 9a³−6a²−13a−1

Answer 1

To obtain (4a³+2a²+7a−4) from (a³−4a²−6a−5), we need to add the corresponding coefficients of each term. The correct option is d) 9a³−6a²−13a−1.

Step-by-step explanation:

To obtain (4a³+2a²+7a−4) from (a³−4a²−6a−5), we need to add the corresponding coefficients of each term. Adding the coefficients of the cubes, squares, and linear terms, and the constant term, hence we get:

a³ + 2a² + 13a - 9

Therefore, the correct option is d) 9a³−6a²−13a−1.