Answer:
[tex](a)\ d'(x) = x + 32[/tex] i.e. The inverse function
[tex](b)\ d'(10) = 42[/tex] i.e. The French size of a dress if it is U.S. size 10 is 42.
Step-by-step explanation:
Given
[tex]d(x) = x - 32[/tex]
Solving (a): The inverse function
[tex]d(x) = x - 32[/tex]
Replace d(x) with y
[tex]y = x - 32[/tex]
Swap y and x
[tex]x = y - 32[/tex]
Make y the subject
[tex]y = x + 32[/tex]
Replace y with d'(x)
[tex]d'(x) = x + 32[/tex]
Hence, the inverse function is: [tex]d'(x) = x + 32[/tex]
Solving (b): US size of 10
[tex]d'(x) = x + 32[/tex]
Substitute [tex]x =10[/tex]
[tex]d'(10) = 10 + 32[/tex]
[tex]d'(10) = 42[/tex]