Part A. You have the correct first and second derivative.
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Part B. You'll need to be more specific. What I would do is show how the quantity (-2x+1)^4 is always nonnegative. This is because x^4 = (x^2)^2 is always nonnegative. So (-2x+1)^4 >= 0. The coefficient -10a is either positive or negative depending on the value of 'a'. If a > 0, then -10a is negative. Making h ' (x) negative. So in this case, h(x) is monotonically decreasing always. On the flip side, if a < 0, then h ' (x) is monotonically increasing as h ' (x) is positive.
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Part C. What this is saying is basically "if we change 'a' and/or 'b', then the extrema will NOT change". So is that the case? Let's find out
To find the relative extrema, aka local extrema, we plug in h ' (x) = 0
h ' (x) = -10a(-2x+1)^4
0 = -10a(-2x+1)^4
so either
-10a = 0 or (-2x+1)^4 = 0
The first part is all we care about. Solving for 'a' gets us a = 0.
But there's a problem. It's clearly stated that 'a' is nonzero. So in any other case, the value of 'a' doesn't lead to altering the path in terms of finding the extrema. We'll focus on solving (-2x+1)^4 = 0 for x. Also, the parameter b is nowhere to be found in h ' (x) so that's out as well.
Let us assume the number to be = x
Then
(80/100) * x = 56
4x/5 = 56
4x = 56 * 5
4x = 280
x = 280/4
= 70
The value of the unknown number is 70. I hope the procedure is clear enough for you to understand. You can always use this method for solving similar problems in future without requiring any help from outside. Only thing that needs to be taken care of is the calculation part.
24
Three times as many as four - 3(4) / 4*3/ 4+4+4
4 x 3 = 12
Then for 2 more 4 packs, it'd be 8 since it's either 2*4 or 4+4 (both equal eight)
And then you'd add them both together, 12+8=20
But since it's asking for both Asa and his friend's total amount, you'd add four more to it since 20 is just his friend's amount.
Answer: 2 units left and 3 units up
Step-by-step explanation: