I disagree with instructor's answer

Jomo

Elite Member
Someone asked me this problem and I get a different answer than their professor.
The EXACT wording is : g (f (x)) =? if f = sin and g is the function which calculates the diameter of a circle given its radius.

If I understand the function g, then g(x) = 2x. Hence g(sin(x)) = 2sin(x). However the instructor claims that g (f (x)) = 2pi*sin(x).

Who is correct? If the instructor is correct then please state why.

Thanks!

g (f (x)) =? if f = sin and g is the function which calculates the diameter of a circle given its radius.

Last edited:

Harry_the_cat

Senior Member
Someone asked me this problem and I get a different answer than their professor.
The EXACT wording is : g (f (x)) =? if f = sin and g is the function which calculates the diameter of a circle given its radius.

If I understand the function g, then g(x) = 2x. Hence g(sin(x)) = 2sin(x). However the instructor claims that g (f (x)) = 2pi*sin(x).

Who is correct? If the instructor is correct then please state why.

Thanks!
g(f(x)) = 2 sin(x) where g is the
function which calculates the diameter of a circle given its radius.

g(f(x)) = 2 pi *sin(x) where g is the function
which calculates the circumference of a circle given its radius.

Jomo

Elite Member
g(f(x)) = 2 sin(x) where g is the
function which calculates the diameter of a circle given its radius.

g(f(x)) = 2 pi *sin(x) where g is the function
which calculates the circumference of a circle given its radius.
That is just what I thought.