Suppose f and g are continuous functions such that g(8) = 2 and the limit as x approaches 8 [3f(x) + f(x)g(x)]= 30.

Find f(8). Do you treat f(8) as if it is a variable and solve for it?

Question

Suppose f and g are continuous functions such that g(8) = 2 and the limit as x approaches 8 [3f(x) + f(x)g(x)]= 30.

Find f(8). Do you treat f(8) as if it is a variable and solve for it?

anonymous · Answer

yes.

you have 3f(8) + f(8)g(8) = 30

3f(8) + 2f(8) = 30
5f(8) = 30

anonymous · Answer

okay so i got that but now im confused
i was given this question:
Suppose f and g are continuous functions such that 
g(4) = 2
 and 
lim 
x → 4 
[3f(x) + f(x)g(x)] = 25.
 Find 
f(4).

Im stuck at this step:
25=[3f(4) + f(4)(2)]
Help Me!!

anonymous · Answer

3f(4) + 2f(4) = 5f(4)

anonymous · Answer

I never understood that step. seeing it really helped. your awesome, Thank You. ^_^

anonymous · Answer

glad i could help :)