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Wolfie1963
Sep 18, 2007, 09:32 PM
My equation is this
y = cot x
This was a sample question in my online review.

I have all the x's as x1 = 0, x2= pi/8, x3= pi/4, x4= 3pi/8, x5= pi/2, x6= 5pi/8,
x7= 3pi/4, x8= pi.

These are all in the lesson plan. The y's are as follows y1= domain, y2= 2.41, y3= 1,
y4 = 0.41, y5 = 0, y6 = -0.41, y7 = -1, y8 = -domain.

my question is this how do they come up with the 2.41 for the y2 in the equation.

the lesson plan show them getting it as cot pi/8 = 1/tan(pi/8) = 1/.041 = 2.41.

can anyone show me what was done to get this answer. I am so confused and doing this online.
Thanks Cindy

ebaines
Sep 19, 2007, 05:41 AM
Recall that cot(x) is defined as 1/tan(x), or as cos(x)/sin(x). Plug pi/8 in for x, and you get your answer.