Ok.. so I have a very basic trig question i am trying to figure out. I missed 2 days of class last week and am completely lost here is the question: sin40 + sin130 + sin220 + sin310 use definition I know the answer is 0.. just need to know why and how to calculate w/o a calculator x__x I really wish i woulda gone to class now
Lol SinCos and Tangent are all basically codenames for A B and C (respectively i think, or it depends on the problem). I think tangent is always the hypotonuse, while the problem will normally tell you if your using Sin or Cos to solve the problem. Using a graphing clacultor is very useful for figuring out these problems. I don't know the answer to your question but I know google has some really good calculators.
Sketch the graph and all is obvious. Let sin40 = A Draw a dashed line at 90 degrees. (the middle of the first bump) And you'll see the graph is symmetricla either side of that. Therefore sin130 gives the same answer as sin(130-90)=sin40 Now sin220 if you observe again it's symmetrical but upside down, you get that sin220=-sin(40), again sin310 is the same as sin220 which is the same as -sin40. so you have sin40+sin40-sin40-sin40=0
Ahh Soc beat me to it. These basic trig questions usually simplify and cancel out to something extremely simple
Hehe.. thx i ended up looking this up a few hours before the hw was due and forgot to check this. but i'll rep you anyways ^^