Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Calculus review!

  1. Dec 17, 2003 #1
    Hi guys, I have a calculus test tomorrow and it'll be great if I can recieve some answers + explanations! my review sheet is attached. if this is breaking the rules im sorry.

    hope this actually helps some other people too

    Attached Files:

    Last edited: Dec 17, 2003
  2. jcsd
  3. Dec 17, 2003 #2
    for #1
    i got 3x^2-sin(xy^2)*2xy [dy/dx]*y^2
    whadaya thinks?
  4. Dec 17, 2003 #3
    for #2) its log(x)/log4 b)then graph it with my TI89 then find the deriv @ .4

    at work right now so no calculator on me =)
    btw: does the TI89 have a test function == like the ti86?
  5. Dec 17, 2003 #4
    #3) f'(x)=2+cosx so we have to prove f'(x) is constantly positive or negative.. but how would we approach that?
  6. Dec 17, 2003 #5


    User Avatar
    Science Advisor
    Homework Helper

    What's the minimum of cos(x) (assuming x is real)
  7. Dec 17, 2003 #6
    sorry im not quite following you. on the y axis it is -1, and on the x it can be -infinite. please correct me if im wrong
  8. Dec 17, 2003 #7


    User Avatar
    Science Advisor
    Homework Helper

    So, if the minimum value of cos(x) is -1, what is the minimum value of 2+cos(x)?
  9. Dec 17, 2003 #8
    lol wow i feel so dumb

    thanks onward to the next question after i finish some quick job for my boss.
  10. Dec 17, 2003 #9
    i got x-4=y^3+y
    so turn my ti89 to parametric mode and y1 = t^3+t
    y2= -1 right? (since its g(3) 3-4 = -1)
    then i trace for a zero?
    Last edited: Dec 17, 2003
  11. Dec 18, 2003 #10
    just came back from my test and i got confused on a question... find the deriv of x+sin(xy) i got (-sec(x)-y)/x but the calc gave me 1

    thanks to all the people that replied and (attempted to) help
  12. Dec 18, 2003 #11
    d/dx{x+sin(xy)} = 1 +cos(xy)[xdy/dx+y]
  13. Dec 19, 2003 #12
    oh my goddd what did i do!?! i messed up.. oh wells :smile:
    thanks himanshu121 for reminding me of my errror
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook