If #f(x)=(ax)/(a+3x), how do you find and simplify f(a)?

1 Answer
Aug 3, 2016

#a/4#

Explanation:

f(x) is a function in x with a being a constant. That is a numeric value.

f(a) assigns a value of 'a' to x.

To evaluate f(a), substitute x = a into the function.

#f(x)=(ax)/(a+3x)#

#rArrf(a)=(axxa)/(a+3xxa)=a^2/(a+3a)=a^2/(4a)#

We can now 'cancel' an a from numerator/denominator

#a^2/(4a)=cancel(a^2)^a/(4 cancel(a)^1)=a/4#