Question

Find the value of expression the a cube– 3a² + 5a – 7 by substituting a = 3.​

Answer 1

Step-by-step explanation:

substitute value a=3 in given equation

$- 3 \times {3}^{2} + 5(3) - 7 \\ = - 3 \times 9 + 15 - 7 = - 27 + 15 - 7 \\ = - 34 + 15 \\ = - 19$