00:01
Okay, so here we're going to use the formula cosine of k plus 1 theta equals cosine of k theta times cosine of theta minus sine of k theta times sine of theta and sine of k plus 1 theta equals sine of k theta, cosine of theta plus cosine of k theta, plus cosine of k theta, times sine of theta.
00:44
Okay, so we can answer from question, uh, question a, we will determine a squared, so that we have a cosine theta, sine theta, negative sine theta, cosine theta, cosine theta, cosine theta, cosine theta, sine theta, sine theta, cosine theta, plusine squared theta, minus sine squared theta, theta, and cosine theta, sine theta, plus, cosine, theta, plus, cosine, theta, sin, theta, negative, cosine, theta, sine, theta, negative, cosine, theta, and cosine theta, excuse me, sine squared of theta, plus cosine squared of theta, okay, so so using the double angle formula, we obtain cosine of 2x, sine of 2x, negative sign of 2x, and cosine of 2x.
02:28
Now, we can do question b.
02:39
A cube equals a squared times a...