.
go thru both once
but why are you dividing both top and bottom by sin(x)cos(x)?
ok..
cuz we want 1 in the top
idk the actual q... just looking at that work, it appears like we want to have 1 in the top.....
Ok,mind if i work it out again?
ha
problem: \[\large (\sec(x)-\cos(x))(\csc(x)-\sin(x)) = \frac{1}{\tan(x) +\cot (x)}\] \[\large \left( \frac{1}{\cos(x)}- \cos(x) \right ) \left( \frac{1}{\sin(x)} -\sin(x)\right)\]\[\large \left(\frac{1-\cos^2(x)}{\cos(x)}\right) \left(\frac{1-\sin^2(x)}{\sin(x)}\right)\]\[\large \left(\frac{\sin^2(x)}{\cos(x)}\right)\left(\frac{\cos^2(x)}{\sin(x)}\right)\]\[= \large \frac{\sin(x)\cos(x)}{1}\]\[=\large \frac{\sin(x)\cos(x)}{\sin^2(x)+\cos^2(x)}\]\[\large \frac{1}{\frac{\sin(x)\cos(x)}{\sin^2(x)+\cos^2(x)}}\] \[\huge \frac{1}{\frac{1}{\frac{\sin(x)\cos(x)}{\sin^2(x)+\cos^2(x)}}}\]\[\large \frac{1}{\frac{\sin^2(x)+\cos^2(x)}{\sin(x)\cos(x)}}\]\[\large \frac{1}{\tan(x)+\cot(x)}\]
got it now... its an identity :) nice...
Oh I see. if two sides in a triangle are congruent, then the 3rd side must be congruent as well :) Cool.
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Oh I just think of a circle..
:)
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For these triangles to be congruent by SAS, the included also has to be congruent. else they can open up to anything and the triangles cannot be congruent/similar.
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