let y = (x+7)/(x+5)
to form the inverse, interchange the x and y variables, thus
x = (y+7)/(y+5)
xy + 5x = y + 7
xy - y = 7 - 5x
y(x-1) = 7-5x
y = (7-5x)/(x-1)
so f-1(x) = (7-5x)/(x-1)
and
f-1(-3) = (7-5(-3))/((-3)-1)
= 22/-4 = -11/2
Let f(x)=(x+7)/(x+5). inverse f-1(-3)=...
3 answers
f-1(-3) = (5-7(-3))/((-3)-1)
= 26/-4 = -13/2
thanks!
= 26/-4 = -13/2
thanks!
nope!
checking :
subbing my answer of -11/2 back in the original function yields -3
Your answer of -13/2 does not.
checking :
subbing my answer of -11/2 back in the original function yields -3
Your answer of -13/2 does not.