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## Homework Statement

(1)

Real variables x and y are related by the equation

3ln(y +4) = 2ln(x +2) − 2ln(x +9)+3ln(x^2 − 1).

Determine the range of values of x and y for which the expressions on each side of this equation are defined.

Find y explicitly as a function of x, that is, express the equation in the form y = f(x), simplifying your answer as far as possible.

(2)

Show that the expressions √3cos(5t + π/6) and (√3/2)(√3cos(5t) − sin(5t)) are equivalent.

## Homework Equations

None

## The Attempt at a Solution

(1)

I assume y must be > -4 to make the ln of a real number. As for x I have no idea which one to use, do I have to expand them somehow? Or is it simply x^2 > 1 and x > -9 and x > -2 leaving us with the lowest x > -9

(2)

Uhm.... no idea really, please give me a clue. Something tells me its substituting identities and simplification.