Question 665802
If cos(t)=-3/4 where pi<t<3pi/2, find the values of the following trigonometric functions. 
Note: Give exact answers, do not use decimal numbers. The answer should be a fraction or an arithmetic expression. If the answer involves a square root it should be enter as sqrt; e.g. the square root of 2 should be written as sqrt(2).
cos(2t)= 
sin(2t)= 
cos(t/2)= 
sin(t/2)= 
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Look up "half-angle formula" on Wikipedia.  It has the double angles also.