Question

(6c-5)(6c+5)-(6c-5)^2 при c=11

Answer 1

( 6c - 5)(6c + 5) - (6c - 5)² = 36c² - 25 - (36c² - 60c + 25) = 36c² - 36c² - 25 - 25 + 60c=
= 60c - 50
При c = 11:
60c - 50 = 60×11 - 50 = 660 - 50 = 610.