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Hard Maths Question Help?

klip
(edited 6 years ago)
Original post by opi453
Assume that f and g are differentiable on the interval (−c, c) andf(0) = g(0).

(1) Show that if f '(x) > g'(x) for all x (0, c), then f(x) > g(x) for all x (0, c).

(2) Show that if f '(x) > g'(x) for all x (−c, 0), then f(x) < g(x) for all x (−c, 0).

Was thinking of using CMVT, but how would you know that g'(x)is not zero at one point

Consider the function f-g, and you can use standard results involving just the plain MVT rather than CMVT.
Reply 2
Original post by Smaug123
Consider the function f-g, and you can use standard results involving just the plain MVT rather than CMVT.


How so?
Reply 3
Original post by Smaug123
Consider the function f-g, and you can use standard results involving just the plain MVT rather than CMVT.


What about using l hopitals rule
Original post by opi453
What about using l hopitals rule


Can you please state L'Hôpital's rule for me?
Reply 5
jui
(edited 6 years ago)
Original post by opi453
, and exists, and for all x in I with x c,then
.


How might it help?

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