Originally posted by genius tricky little trig problem that i found today. that is, it was in my exam...woo...

show that tan(3x) = (3*tan(x)-tan(x)^3)/(1-3*(tan(x)^2)

wtf??? ... and I felt bad because I messed up my physics exam on thursday (that is, really messed it up as in nearly every question wrong...). Did you get the right answer in the exam, btw?
Angie ðŸ™„ðŸ˜²ðŸ™„ðŸ˜²ðŸ™„ðŸ˜²ðŸ™„ðŸ˜²

PS: I hate physics... and I have a maths exam on tuesday, so I'll just ask you if I have questions beforehand ðŸ˜€

Originally posted by Acolyte Use the formula for tan(A+B) ( (tanA + tanB)/(1-tanAtanB) or something) and turn the handle - standard Higher/A-Level question. ðŸ˜´

erm-i meant to add in "using De Moivres theorem". sorry ðŸ˜›