Search 75,514 tutors
Ask a question

Answers by Kay H.

How would I find the cosine of a fraction of a variable? (answer)

You need to use trig identities. There is the double angle cos 2€ and 1/2 angle  identity cos 1/2€. If you can get your fraction to fit into one of these formulas you should be able to solve it from there. For example, if you have cos 1/4@ you could rewrite it as cos 2(1/8)@. The identity...

f(x)=x^2/3 * (2-x) = x^2/3 * (2-x) (answer)

Robert's answer looks good.  If, however, the 3(2-x) is in the denominator, then try this:   f(x) = x^2 / (6-3x)   Use Chain Rule where a = x^2 and b = (6-3x)^-1   f'(x) = ab' + ba' f'(x) = (x^2)(-1)(-3)(6-3x)^-2 + 2x(6-3x)^-1 f'(x) = (3x^2)/(6-3x)^2...

Number line and Interval Notation (answer)

Ok, good job. X is less than -7 is correct. On a number line you have the negative numbers, zero, then the positive numbers to the right. Right? So to plot x<-7 we need an open circle on negative seven. This is because x cannot be equal to negative seven, it has to be less. So x could be -7...