SOLUTION: Find the slope of the curve 3x^2-y^2=12 if x=4.

Algebra ->  Linear-equations -> SOLUTION: Find the slope of the curve 3x^2-y^2=12 if x=4.      Log On


   



Question 650758: Find the slope of the curve 3x^2-y^2=12 if x=4.
Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!
3x² - y² = 12

6x%28dx%29%2F%28dx%29 - 2y%28dy%29%2F%28dx%29 = 0

6x(1) - 2y%28dy%29%2F%28dx%29 = 0
6x - 2y%28dy%29%2F%28dx%29 = 0
    -2y%28dy%29%2F%28dx%29 = -6x
       %28dy%29%2F%28dx%29 = %28-6x%29%2F%28-2y%29
       %28dy%29%2F%28dx%29 = 3x%2Fy

To use that, we must find y when x = 4

  3x² - y² = 1
3(4)² - y² = 1 
 3*16 - y² = 1
   48 - y² = 1
       -y² = -47
        y² = 47
         y = %22%22+%2B-+sqrt%2847%29

       %28dy%29%2F%28dx%29 = 3x%2Fy, substitute (4,%22%22+%2B-+sqrt%2847%29)
       %28dy%29%2F%28dx%29 = 3%284%29%2F%28%22%22+%2B-+sqrt%2847%29%29
       %28dy%29%2F%28dx%29 = %22%22+%2B-+12%2Fsqrt%2847%29

Edwin