Function Operation

Question

f(x)=x^1/2, g(x) = 4x^1/4, and h(x)=-4.9√x

 

Find (fg)(x) and (fg)(1)

Answer 1

(fg)(x) means plug x into the x value of each function, then multiply the two functions. (fg)(x)= (x^1/2)(4x^1/4)=4x^3/4.  When you multiply variables with exponents, you add the exponents.

 

(fg)(1) means plug 1 into your variable of x, then multiply the functions. (1)^1/2 is 1 and 4(1)^3/4 is 4, so 1(4) is 4.