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sim0nz12345
Feb 9, 2008, 05:50 PM
Hi there, I previously asked a question concerning ranges: How would I start on this one using calculas.

f(x)=5-2^(cos)x, -Pi/2<x<equal to 0

Anyhelp would be appreciated

jiten55
Feb 9, 2008, 05:58 PM
What is the QUESTION?

sim0nz12345
Feb 9, 2008, 07:47 PM
Lol I forgot abou that.

THe question asks me to find the domain and range of it. Thanks
I don't know what A lies between in cosine.

jiten55
Feb 9, 2008, 09:38 PM
First step:

Find Maxima and Minima

Equate first derivative to zero, to get the values of x to be tested

When second derivative is negative, you have maxima

When second derivative is positive, you have minima

Remember: Derivative of a^g(x) = a^g(x) log a times [derivative of g(x)]

Range of the function, by definition, is between the least and greatest value of f(x):

1. Find minimum and maximum values of function in the domain.

2. Find values of the function at end points of the domain.

3. Greatest value = Greatest of the above values. (in step 1 and 2)

4. Least value = Least of the above values (in step 1 and 2)

5. Range = [Least value, Greatest Value]


GIVE THE ABOVE A TRY, AND REVERT IF YOU NEED FURTHER HELP.