Answer:
cosA = √(21/25)
Step-by-step explanation:
We know
sin²(A) + cos²(A) = 1
Next, we know that sin(A) = 2/5. Plugging that into our equation, we get
(2/5)² + cos²A = 1
4/25 + cos²A = 1
subtract 4/25 from both sides to isolate cos²A
cos²A = 1 - 4/25 = 25/25-4/25 = 21/25
square root both sides to get
cosA = √(21/25)
We do not include -√(21/25) in our possible answer for cosA because this is in quadrant 1, so cosA must be positive.
A is the answer because if you calculate the answer correctly. that will be so.
Answer:
obtuse cant be a right angle
Step-by-step explanation:
in order to be obtuse you have to be more than 90 dagrees
Note that f(1) = 6(1)+2 = 8. Next, evaluate g(x) at x=8: g(f(1)) = g(8) = 2(8) + 4/5, or 16 4/5.
9.43 x 10^12 is the answer