Question

√5 is an irrational number. which of these will also be an irrational number? A. (√5)^2 B. (√5)^-2 C. √5 + √5 D. (5+ √5)(5-√5)

Answer 1

Answer:

C.√5 + √5

Step-by-step explanation:

√5 + √5 is an irrational number because

√5 + √5 = 2×√5. √5 is an irrational number and if we multiply it by a number n, the result is always irrational

the other results ( A, B, D ) are rational numbers

A. (√5)^2 = 5

B. (√5)^-2 = 1 ÷ [(√5)^2] = 1 ÷ 5 = 0.2

D. (5+ √5)(5-√5) = 25 - 5 = 20