Question 77

$$(2x + 5)^{2} \times (4x-1) - (3x^{3} -16x^{2} + 25x -21)$$

Solution

Expression : $$(2x + 5)^{2} \times (4x-1) - (3x^{3} -16x^{2} + 25x -21)$$

= $$[(4x^2 + 20x + 25) \times (4x - 1)] - (3x^3 - 16x^2 + 25x - 21)$$

= $$[(16x^3 - 4x^2) + (80x^2 - 20x) + (100x - 25)] + (-3x^3 + 16x^2 - 25x + 21)$$

= $$(16x^3 - 3x^3) + (80x^2 - 4x^2 + 16x^2) + (100x - 25x - 20x) + (-25 + 21)$$

= $$13x^3 + 92x^2 + 55x - 4$$

Share on Whatsapp Share on Whatsapp

Create a FREE account and get: