D. It Is The Most Fitting Answer. The Other 3 Equal More Than Needed.
To get the extrema, derive the function.
You get y' = 2x^-1/3 - 2.
Set this equal to zero, and you get x=0 as the location of a critical point.
Since you are on a closed interval [-1, 1], those points can also have an extrema.
Your min is right, but the max isn't at (1,1). At x=-1, you get y=5 (y = 3(-1)^2/3 -2(-1); (-1)^2/3 = 1, not -1).
Thus, the maximum is at (-1, 5).
Time taken by Michelle to complete the work alone = 6 hours
Time taken by Nancy to complete the work alone = 3 hours
Now, when they both are working on the same job for 1 hour,
Amount of job completed = (1/6) + (1/3)
= (1 + 2)/6
= 3/6
= 1/2
So in 1 hours time they both will complete half of the job. Then in 2 hours Michelle and Nancy will complete the total job. I hope the answer has come to your help.
0.9^50=0.0051537752That's your answer.<span>
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