Question

Simplify (x - square root 7)^2

Answer 1

Answer:

x^2 + -2 sqrt(7) x + 7

Step-by-step explanation:

Expand the following:

(x - sqrt(7))^2

(x - sqrt(7)) (x - sqrt(7)) = (x) (x) + (x) (-sqrt(7)) + (-sqrt(7)) (x) + (-sqrt(7)) (-sqrt(7)):

x x - sqrt(7) x - sqrt(7) x - (-sqrt(7) sqrt(7))

(-1)^2 = 1:

x x - sqrt(7) x - sqrt(7) x + (sqrt(7))^2

x x = x^2:

x^2 - sqrt(7) x - sqrt(7) x + sqrt(7)^2

Cancel exponents. (sqrt(7))^2 = 7:

x^2 - sqrt(7) x - sqrt(7) x + 7

Combining like terms, sqrt(7) x (-1) + sqrt(7) x (-1) = -2 sqrt(7) x:

Answer:  x^2 + -2 sqrt(7) x + 7