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Question

If r^2+1=-2r, then (r+½)^2=

a. -1/4

b. 1/4

c. 1

d. cannot be determined

Answer 1

Since r² + 1 = -2r, r² + 2r + 1 = 0

So, (r + 1)² = 0. Therefore, r = -1.

So, (r+1/2)² = (-1/2)² = 1/4