Magellan

Discussion (2) ¬

1. 
   David Nuttall

   June 17, 2020, 11:48 am | # | Reply

   Let’s see.
   g(x) = sqrt(x) * f(x)
   g'(x) = 1/sqrt(x) * f(x) + f'(x) sqrt(x)
   g'(4) = 1/sqrt(4) * f(4) + f'(x) sqrt(4)
   g'(4) = 1/2 * 3 + 5 * 2
   g'(4) = 0.75 + 10
   g'(4) = 10.75
   Way to go Fatima.

   • 
     David Nuttall

     June 17, 2020, 11:54 am | # | Reply

     Oh wait, I goofed the square root rule and some of the simplifying. I think I got suckered by a confirmation bias.
     sqrt(x) = x^(1/2)
     d sqrt(x)/dx = (1/2) x^(-1/2) = 1/(2sqrt(x))
     Therefore,
     g'(x) = f(x)/(2sqrt(x)) + f(x) sqrt(x)
     g'(4) = f(4)/(2sqrt(4)) + f(4) sqrt(4)
     g'(4) = 3/(2*2) + 5 * 2
     g'(4) = 3/4 + 10
     g'(4) = 10.75