Quick questions: What is cos multiplied by cos and what is cos divided by cos
let cos = x now what's x times x and what is x divided by x ?
x^2
x divided by x equals 1?
right so cos times cos would be \(\large\rm {cos^2 \theta}\)
\[\rm \sin^2 \theta +\cos^2 \theta =1\] this is a special identity which can be written as \[\cos^2 \theta = 1-\sin^2 \theta\] so to verify identity you can replace cos^2 with 1-sin^2
eh but that wasn't your question and yes x/x =1 so cos/cos =1
and does the same principle apply to sin also?
we are using exponent rules here \[\rm \huge\rm x^m \times x^n =x^{m+n}\] multiply same bases so add their exponents \[\huge\rm \frac{ x^m }{ x^n }=x^{m-n}\] when we divide same bases we should subtract their exponents
and yes right sin is same as sin to the one power \[\frac{ \sin^1 }{ \sin^1 } =\sin^{1-1} = \sin^{0}=\sin \theta\] anything to the zero power equal to one
and when we multiply same bases \[\huge\rm sin^{1} *\sin^{1} =sin^{1+1}=sin^{2} theta \]
wait, sin/sin=sin?
same thing just like cos
what would you get when you divide same bases ?
like 2/2 ,5/5 y/y
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