Trigonometric identities

With 180° < θ < 270°, we know that both cos(θ) < 0 and sin(θ) < 0.

Then from the Pythagorean identity, it follows that

sin²(θ) + cos²(θ) = 1   ==>   sin(θ) = -√(1 - cos²(θ))

and so

sin(θ) = -√(1 - (-8/13)²) = -√105/13

Recall the double angle identity for sine:

sin(2θ) = 2 sin(θ) cos(θ) = 2 (-√105/13) (-8/13) = 16√105/169

step-by-step explanation:

i believe its "c" because all of the other options include a but it could be d because there is a way of financing with cash at certain places but its uncommon.

0.6, 3/5, and 6% are the 3 same portion.

but, when they're all changed to a decimal they would equal to 0.6.

hope this , good luck!