Posted by katie on .
For the following expression, find the value of y that corresponds to each value of x, then write your results as ordered pairs (x,y).
y=7cos(xpi/6) for x=pi/6, pi/3, 2pi/3, pi, 7pi/6

trig 
Reiny,
I will do the first one, you do the others.
Let me know what you get.
y = 7cos(xπ/6) , for x = π/6
= 7cos(π/6  π/6)
= 7cos 0
= 7(1) = 7
one more... if x = 2π/3
y = 7cos(2π/3  π/6)
= 7cos (π/2)
= 7(0) = 0 
trig 
katie,
i didn't realize it was just plugging in! thanks! i just need to figure out how to subtract fractions with pi in them now

trig 
katie,
pi/3 is 7 square root 3/ 2 pi is  7 square root 3 / 2 and 7pi/6 is 7

trig 
Reiny,
I don't like the way you wrote those answers
Be mathematically correct, ..... e.g.
if x = π/3
y = 7cos(π/3  π/6)
= 7 cos (π/6)
= 7(√3/2) = 7√3/2
if x = 7π/6
y = 7cos(7π/6  π/6)
= 7cos π
= 7(1) = 7
A statement such as "π/3 is 7√3/2" makes no sense