Question

f(x)=2+3 cos(π/10)(x−3) Find f(2.6)
Please help I keep getting an answer thats not one of my choices!!!

Answer 1

what are your choices?

Answer 2

A. -.06842
B. 2.6
C. 4.9763
D. 5

Answer 3

are you getting -6.999973133?

Answer 4

no im getting 0.858732

Answer 5

how are you getting that? i am just trying to find the mistake

Answer 6

I'm putting it into my calculator but then i put it into wolfram alpha and i got the same thing

Answer 7

how are you putting it into your calculator?

Answer 8

You're probably messing up your order of operations somewhere.
Or perhaps you're in degree mode by mistake.
Trying entering it like this:
\[2+3\times \cos\left(\left(\pi\div10)(2.6-3\right)\right)\]

Answer 9

wow i got 4.999 so 5 thanks:)

Answer 10

Hmm as I said before, you're in degree mode.
Fix that.

Answer 11

You want to be in Radians*