Question

5. (n-1) (n-6).....Tell me fast ​

Answer 1

Answer:

Here, x = n, a = -1 and b = -6.

$(x + a)(x + b) = {x}^{2} + (a + b)x \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: + ab$

$(n - 1)(n - 6) \\ = {(n)}^{2} + ( - 1 - 6) n+ ( - 1) \\ \: \: \: \: \: \: \times ( - 6) \\ = {n}^{2} - 7n + 6$