Question

What did I do wrong? Ans from book: http://i.imgur.com/UhH5l.gif My work: http://mathb.in/466

Answer 1

you didnt do anything wrong, you got the same answer

Answer 2

you just didnt rationalize your answer, you left it as 1/(sqrt3)

to rationalize, multiply both top and bottom by sqrt3

then you will have the same answer as the other person

Answer 3

and good work btw much faster solution lol

Answer 4

Wait, what about the cot solutions he had?

Answer 5

Reddit says this: http://www.reddit.com/r/cheatatmathhomework/comments/ujq6w/double_angle_work_check/

Answer 6

I don't see how I can look out for me eliminating a solution set through fractions.

Answer 7

well, in the original question there was tanx and cotx, which is a good indication of what may be in the solution.

what im actually looking for is a way to substitute something back into the original equation, or some way down, and you'll end up with just cotx = 0.

cause, in your very first line, you have something set = cotx, if you can say that = 0, then you have your finished solution.

Answer 8

otherwise, i think you need to follow the other guy's solution

Answer 9

Reload reddit. Someone has a nice response.

Answer 10

i was about to say that lol, running into a problem of dividing by zero. I assume, that when the problem was written there was no given tanx or cotx is or is not equal to zero. But the problem was set = 0, and indeed have to assume cotx might = 0 until the very end.

Answer 11

Thanks!