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Confused_111
Nov 3, 2007, 05:57 AM
How would you do this question please:

The oestrogen level in a mature female gorilla is given by the function y=70+50sin[(pi t)/6] where y is the number of units of oestorgen (t) days after the beginning of her oestrous cycle.

If she can conceive only when her oestrogen level exceeds 110 units, on approximately how many days of her oestrous cycle can she conceive?

Note its pi times t in the brackes
This question stumped me

Thanks

galactus
Nov 3, 2007, 06:51 AM
Another inequality like the other problem. Solve the same way.

Confused_111
Nov 3, 2007, 06:58 AM
Does solving this inequation invole drawing a graph for circular functions

galactus
Nov 3, 2007, 07:17 AM
No, just some algebra.

70+50sin(\frac{{\pi}t}{6})>110

Confused_111
Nov 3, 2007, 06:26 PM
Thanks but how would you solve this inequation, teacher never explained it thoroughly. I appreciate your help so far Thanks

galactus
Nov 3, 2007, 06:51 PM
I suppose you could graph it and look for the points where it is > 110.

70+50sin(\frac{{\pi}t}{6})>110

50sin(\frac{{\pi}t}{6})>40

sin(\frac{{\pi}t}{6})>\frac{4}{5}

\frac{{\pi}t}{6}>sin^{-1}(4/5)

t>\frac{6sin^{-1}(4/5)}{\pi}