Distributing Cos45 in an Expression: Numerator and Denominator

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Ryuk1990
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Let's say I have an expression like this.

cos45[(601-148)/sin21.8]

Does cos45 get multiplied into just the numerator terms or do I also distribute it to the denominator as well?
 
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Only the numerator. Think of it as cos(45)/1 so that cos(45) multiplies the numerator and 1 multiples the denominator.

Also, notice that cos(45) equals something simple.
 
Multiplying into the numerator and the denominator would give you [tex]\frac{cos(45)(601-148)}{cos(45)sin(21.8)}[/tex] and the cosines would cancel which is not what you want.