Suppose a triangle has sides a, b, and c, and let be the angle opposite the side of length a. If cos < 0, what must be true?
b^2 + c^2 > a^2
a^2 + b^2 = c^2
b^2 + c^2 < a^2
a^2 + b^2 > c^2

would it be A?

Find a parametrization for the curve「and determine the work done on a particle moving along γ in r3 through the force field f: r^3--r^3'where f(x,y,z) = (1,-x,z) and (a) im (γ) is the line segment from (0,0,0) to (1,2,1) (b) im (γ) is the polygonal curve with successive vertices (1,0,0), (0,1,1), and (2,2,2) (c) im (γ) is the unit circle in the plane z = 1 with center (0,0,1) beginning and ending at (1,0,1), and starting towards (0,1,1)