Hi guys, I need some help with a question from the IB HL maths papers. Not sure how this works: Sin(2n+1)xcosx - cos(2n+1)xsinx = sin(2n+1)x - x = sin 2nx Could some1 show me more detailed steps or give me some hints on how equation holds?
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Originally Posted by holaboo Hi guys, I need some help with a question from the IB HL maths papers. Not sure how this works: Sin(2n+1)xcosx - cos(2n+1)xsinx = sin(2n+1)x - x = sin 2nx Could some1 show me more detailed steps or give me some hints on how equation holds? Hang on, is that x in the middle of each term a times or an ? Some spacing and brackets would help ><
oh sorry, all the x are X, not times I'm not sure how to insert mathematic symbols...
Sin(2n+1)x . cosx - cos(2n+1)x . sinx = sin(2n+1)x - x = sin 2nx
Apply with and .
thanks I just worked it out myself too. Is the Sin A-B formula derived from the Sin A+B formula? Could you do the same for the Cos A+B formula?
Originally Posted by holaboo thanks I just worked it out myself too. Is the Sin A-B formula derived from the Sin A+B formula? Could you do the same for the Cos A+B formula? Yes, the formula for is derived from the formula, just letting and remembering that and . And yes, you can derive a formula for using the formula using the same reasoning.
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