SOLUTION: Without using a calculator (answer in radical form and rationalizing the denominator, if necessary), evaluate the following: (a) cot 225(degree) (b)tan(-pi/4) (c)cos 495(d

Algebra ->  Trigonometry-basics -> SOLUTION: Without using a calculator (answer in radical form and rationalizing the denominator, if necessary), evaluate the following: (a) cot 225(degree) (b)tan(-pi/4) (c)cos 495(d      Log On


   

Question 852944: Without using a calculator (answer in radical form and rationalizing the denominator, if necessary), evaluate the following:
(a) cot 225(degree)
(b)tan(-pi/4)
(c)cos 495(degree)
(d)sec 225(degree)
(e) cot 30(degree)
(f) sin pi
I really need help with this. Please!
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Using the (cosx,sinx) summary below for reference:

(a) cot 225(degree) = cos225/sin225 = 1

 (b)tan(-π/4) = -tan π/4  = -sin π/4/cos π/4= -1

 (c)cos 495(degree) = cos 135 = -sqrt%282%29%2F2

 (d)sec 225(degree) = 1/cos225 =-2%2Fsqrt%282%29  

 (e) cot 30(degree) = cos30/sin30 = sqrt%283%29

 (f) sin pi = 0