00:01
Okay, so for this question, what we're going to do is solve a given expression without our calculator.
00:08
So this expression is cosine of pi over 4 plus sine of pi over 6, which is all simply squared.
00:24
So now the first thing we're going to do is figure out what pi over 4 is in degrees.
00:32
So since pi is equal to 180, pi over 4 is 45, and pi over 6 is equal to 30.
00:48
So we can use these values to now create a special right triangle because we should know already that 45 and 30 are both part of two different right triangles.
01:01
So we have this one, 30, 60, and we have this one, which is 45 and 45.
01:16
And then for the 45, 45, 40, 90, that's 1, 1, and square root of 2.
01:21
For 30, 60, 90, we have opposite 30 is 1, opposite 60 is square root of 3, and the opposite 90 is 2.
01:29
So now that we have all the values of the right triangle, if it's not memorized, then we can just simply, solve each trig function.
01:38
So now we're going to do is do cosine of pi over four, which is 1 over squared of 2, plus sine of pi over 6, which is 1 half...