Calculus
posted by Jarred on .
This is my first calculus class and I am lost on how to answer these. The book isn't giving me a clear explanation for help. Any help someone could provide would be great!
1. Use a reference triangle to find the given angle.
cos 1 (1/2) give an exact answer in terms of pi
2. Express In 0.25 in terms of In 2 and In 3. Simplify your answer. Use integers or fractions for any number in the answer.
3. Determine whether the function is even, odd or neither.
f(x)=4x^5 + 3x^3
Thank you!!!!

1. Use a reference triangle to find the given angle.
cos 1 (1/2) give an exact answer in terms of pi
adjacent/hypotenuse = 1/2
well, if you know about 30,60,90 triangle the answer is immediate.
sin 30 degrees = 1/2
cos 60 degrees = 1/2
60 degrees = pi/3 radians 
2. Express In 0.25 in terms of In 2 and In 3. Simplify your answer. Use integers or fractions for any number in the answer.
ln (1/4) = ln 1  ln 4 = 0  ln 4
ln 4 = 2 ln 2 
3. Determine whether the function is even, odd or neither.
f(x)=4x^5 + 3x^3
For negative x, this function is negative of the corresponding value for positive x
Therefore it is ODD
In general odd powers of x are odd and even powers of x are even
eg
f(x ) = +x
f(x) = x odd
f(x ) = + x^2
f(x) = + x^2 even