Use the identity for tan(x-y) = [tan(x) - tan(y)]/[1-tan(x)tan(y)] to show that if two lines L1 and L2 intersect at angle theta then tan(theta) = m2-m1/(1 + m1m2) where m1 and m2 are the slopes of L1 and L2 respectivly.(adsbygoogle = window.adsbygoogle || []).push({});

hmm ihave no idea where to start for this it doesnt make sense to me. plz help

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# Identity for tan(x-y) = [tan(x) - tan(y)]/[1-tan(x)tan(y)]

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