# Trig – So far we have... July 2011. Subject Content = Covered.

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Trig – So far we have... July 2011

Subject Content = Covered

We are working on applications Multistep and practical problems 3 Dimensional problems Setting out the steps in a logical and clear manner, which may include drawing triangles Remember: Similar triangles, angles in a triangle add to 180 degrees and SOH-CAH-TOA and Pythag is ONLY for RIGHT ANGLE triangles!

Pythagoras c 2 = a 2 + b 2 where c is the hypotenuse = the longest side

SOH-CAH-TOA We talked about similar triangles = same angles = scale factor

3D Problems

SOH-CAH-TOA

Pythagoras c 2 = a 2 + b 2 so c = (a 2 + b 2 )^0.5 a 2 = c 2 - b 2 so a = (c 2 - b 2 )^0.5 b 2 = c 2 - a 2 so b = (c 2 - a 2 )^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: H 2 = O 2 + A 2 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

Which Formulae ?

Practical measurement Using a Clinometer

3D Problem Solving

Today: Algebra recap solve for x ax 2 + bx + c = 0 Working on problems in the text book and work book. One group at a time measuring the classroom as per yesterday.

solve for x ax 2 + bx + c = 0