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Trig – So far we have. July 2011. Pythagoras c 2 = a 2 + b 2 where c is the hypotenuse = the longest side. SOH - CAH -TOA. 3D Problems. SOH - CAH -TOA.
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Trig – So far we have... July 2011
Pythagoras c2= a2+ b2 where c is the hypotenuse = the longest side
Pythagorasc2 = a2 + b2 so c = (a2+ b2 )^0.5a2= c2 - b2so a = (c2 - b2 )^0.5 b2= c2 - a2 so b = (c2 - a2 )^0.5
How to label a triangle • H = Hypotenuse, which is always opposite the right angle and always the longest side. It does not move, Pythag: H2 = O2 + A2 • O = opposite which is the side opposite the angle we are interested in. • A = Adjacent which lies between the right angle and the angle we are interested in.
Which formulae do I use? Pythag or SOH-CAH-TOA
Today:Algebra recapsolve for xax2 + bx + c = 0Working on problems in the text book and work book.One group at a time measuring the classroom as per yesterday.
Quad Formula fromhttp://users.rcn.com/mwhitney.massed/quadratic_formula_proof.htmlMs Allan’s Wiki:http://2011maths.wikispaces.com/NCEA+Level+1+Trig