Posted by saad on Monday, August 15, 2011 at 12:32am.
Solve the equation for cos thetatan theta=0 for greater than or egual to zero but less than 2pi. Write your answer as a multiple of pi, if possible form the following choices:
pi , 5pi
A.  
4___ 4
B. pi 3pi 5pi 7pi
 ' ''
4_____ 4_____ 4______4
C. pi 3pi 3pi 7pi
 ' ''
2_______4______2_____4
D. pi 7pi 3pi 11pi
 ' ''
2________6______2_____6

trig  Anonymous, Monday, August 15, 2011 at 2:08am
cos ( theta )  tan ( theta) = 0
tan ( theta ) = sin (theta ) / cos( theta )
cos ( theta )  tan ( theta ) =0
cos ( theta ) = tan ( theta )
cos ( theta ) = sin ( theta ) / cos ( theta )
cos^2 ( theta) = sin ( theta )
Now go on:
wolframalpha dot com
When page be open in rectangle type :
solve cos^2 ( theta) = sin ( theta )
and click =
After few seconds you will see solution.
Then click option Show steps

trig  Reiny, Monday, August 15, 2011 at 8:48am
cosØ  tanØ = 0
cosØ  sinØ/cosØ = 0
multiply by cosØ
cos^2Ø  sinØ = 0
(1  sin^2Ø)  sinØ = 0
sin^2Ø + sinØ  1 = 0
sinØ = (1 ± √5)/2
sinØ = .618034 or 1.608 , the last is not possible since sinØ has to be between 1 and +1
Ø = 38.17° from my calculator (or 141.83°)
All your choices are in radians in multiples of π/2, π/4 or π/6
which would be multiples of 90°, 45° or 30°
None of these match,
btw, my answers satisfies the original equation.
Answer This Question
Related Questions
 trig  Solve the equation for cos(3theta/2).tan(3theta/2)for greater than or ...
 Trigonometry  Thank you STEVE!!!!! Suppose that Cos (theta) = 1/square root 2 ...
 Precalc with Trig  What value(s) of theta (0 less than or equal to theta less ...
 Precalculus check answers help!  1. Which expression is equivalent to cos ...
 trig 26  simplify to a constant or trig func. 1. sec ²utan ²u/cos ²v+sin ²v ...
 Maths complex numbers  Find tan(3 theta) in terms of tan theta Use the formula...
 math  I have a question I have been working on since yesterday and I am not ...
 Math Trig Please Help!!!  Find exact values for all the solutions to the ...
 Math Trig Help  sin theta = x/3, with theta in the first quadrant, find the ...
 science  Sitting on a horizontal track is a mass of 10kg. One end of the track ...
More Related Questions