Question

Find PR such that 0 ≤ PR ≤ 4 and m θ is a maximum. Let a = 2, b = 6, and h = 4. (Round your answer to four decimal places.)
PR = c = (attached file).

Answer 1

so far I got tan(o1) = 2/4-c

tan(o2) = 6/c

arctan(2/4-c) + arctan (6/c)

f'(c) = 2/(4-c)+4) + -6/c^2+36 = 0

2(c^2 + 36) = 6(c^2 -8c + 16+4)

= 4c^2 - 48c - 48? Not sure if it's correct thuis far.

Answer 2

C^2 - 12c + 12 = 0

12 - sqrt(12) = c?

Answer 3

nope!! :(

Answer 4

10 mins to get this done, I'mt tyard.

Answer 5

http://www.wolframalpha.com/input/?i=derivative+of+arctan%282%2F%28%284-c%29%5E2+%2B4%29%29+%2B+arctan+%286%2Fc%29

Answer 6

I guess I was wrong... Trying to do it like the practice.. 5 mins :(.

Answer 7

you are right...

but c^2-12c+12 =0

c= 6+- sqrt(12)

Answer 8

apparently that's not right :(

Answer 9

2.5359

Answer 10

sorry...
\[c= 6-2\sqrt{6}\]

Answer 11

http://www.wolframalpha.com/input/?i=c%5E2-12c%2B12+%3D0

Answer 12

crap missed the deadline :P. I asked the professor if she would allow it but damn... Still got a 95 but :'(.

Answer 13

to get the derivative right ... and mess up a simple quadratic

lol.. that's life

Answer 14

Yuh... I would have done this all last week but my net was dropping left and right, and we had some weird gas smell where the fire dept had to come and couldnt'; find the cause, then our AC broke :'(.

Answer 15

Yuh... I would have done this all last week but my net was dropping left and right, and we had some weird gas smell where the fire dept had to come and couldnt'; find the cause, then our AC broke :'(.