(x - 6)(x - 6)By component wise multiplication
= x(x - 6) - 6(x - 6)
(from above we can see that, x.x = x2, x.(-6)
= - 6x, -6.x = - 6x, and -6.-6 = +36)
= x2 - 6x - 6x + 36
= x2 - 12x + 36
Note: Multiplication of signs is given by-
(+) × (+) = +
(+) × (-) = -
(-)×(+)= -
(-) × (-) = +