► My Trigonometry course: https://www.kristakingmath.com/trigonometry-course

Like all trig identities, half-angle identities help us manipulate trig functions so that they're easier to evaluate. The reason that they're helpful is because we might not know how to find the value of a trig function with a particular argument. But we might easily know the value of half of the argument. So if we can use a half-angle identity to cut the angle in half, then we'll be able to quickly find the value of the entire trig function.

These particular identities are used less than some others, so they might not be worth memorizing. But they can still come in handy in some situtations.

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If you could use some extra help with your math class, then check out Krista’s website // http://www.kristakingmath.com

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Hi, I’m Krista! I make math courses to keep you from banging your head against the wall. ;)

Math class was always so frustrating for me. I’d go to a class, spend hours on homework, and three days later have an “Ah-ha!” moment about how the problems worked that could have slashed my homework time in half. I’d think, “WHY didn’t my teacher just tell me this in the first place?!”

So I started tutoring to keep other people out of the same aggravating, time-sucking cycle. Since then, I’ve recorded tons of videos and written out cheat-sheet style notes and formula sheets to help every math student—from basic middle school classes to advanced college calculus—figure out what’s going on, understand the important concepts, and pass their classes, once and for all. Interested in getting help? Learn more here: http://www.kristakingmath.com

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Tagged under: educational,precalculus, angle,-angle identities,trig identities, ,trig,calculus,trigonometry,Krista King,precalc

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