If c(x) = 5/x - 2 and d(x) = x + 3, what is the domain of (cd)(x)? And, if f(x) = 7 + 4x and g(x) = 1/2x, what is the value of (f/g)(5)?
Solution:
Given functions are c(x) = 5/x - 2 and d(x) = x + 3
we know that d(x) is valid for all values of x
But c(x) is not valid for x = 2
For (cd)(x) = c(x)*d(x) = 5((x) × 3)/x - 2
Domain for (cd)(x) is all values of x except x = 2.
Also given f(x) = 7 + 4x and g(x) = 1/2x
(f/g)(x) = [7 + 4x] / [1/2x] = 2x(7 + 4x) / 1
(f/g)(5) = 2(5)(7 + 4(5)) /1
(f/g)(5) = 10(7 + 20) = 270
If c(x) = 5/x - 2 and d(x) = x + 3, what is the domain of (cd)(x)? And, if f(x) = 7 + 4x and g(x) = 1/2x, what is the value of (f/g)(5)?
Summary:
If c(x) = 5/x-2 and d(x) = x + 3, the domain of (cd)(x) is all values of x except x = 2. And, if f(x) = 7 + 4x and g(x) = 1/2x, the value of (f/g)(5) is 270.
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