James N. answered 05/26/15
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I love to tutor & have Master's degrees in Physics and Philosophy
If by "negative 2, negative 1" you mean (-2, -1), then
(a) this point must be on the curve and
(b) the curve must be 2nd order to have both negative and positive slopes. So:
looking at (a):
(A) f(x) = f(-2) = sqrt ((-2)+ (2-1)) = sqrt(-2 +1) = sqrt (-1) = i <> -1 → (A) is not the answer
(B) f(x) = f(-2) ((-2) + 2)^2 - 1 = (0)^2 - 1 = 0 - 1 = -1 =-1 → (B) could be the answer
(C) f(x) = f(-2) = -1/((-2) + 2) = -1/0 = infinity <> -1 → (C) is not the answer
(D) f(x) = f(-2) = ((-2) + 2)^3 - 1 = 0^3 - 1 = 0 - 1 = -1 = -1 → (D) could be the answer.
looking at (b):
(B) is second order which means it will change slope once (think a parabola which is second oder → (B) could be the answer
(D) is third order, which means it will change slope once → (B) is not the answer.
So the answer is (B)
(a) this point must be on the curve and
(b) the curve must be 2nd order to have both negative and positive slopes. So:
looking at (a):
(A) f(x) = f(-2) = sqrt ((-2)+ (2-1)) = sqrt(-2 +1) = sqrt (-1) = i <> -1 → (A) is not the answer
(B) f(x) = f(-2) ((-2) + 2)^2 - 1 = (0)^2 - 1 = 0 - 1 = -1 =-1 → (B) could be the answer
(C) f(x) = f(-2) = -1/((-2) + 2) = -1/0 = infinity <> -1 → (C) is not the answer
(D) f(x) = f(-2) = ((-2) + 2)^3 - 1 = 0^3 - 1 = 0 - 1 = -1 = -1 → (D) could be the answer.
looking at (b):
(B) is second order which means it will change slope once (think a parabola which is second oder → (B) could be the answer
(D) is third order, which means it will change slope once → (B) is not the answer.
So the answer is (B)