hi!

can someone help explain what happened here (in black marker) that got rid of the h on 3?

thank you!

Try it! Now, try to find the derivative of the function f (x) = 2x2 - 3x + 1 using First Principles. Hide Suggested Answer fil x = lim f(xth)-f (x) h-0 h x = lim- [2(xth ) " - 3(x+h)+1]-[2x2- 3x+1] h -0 f' ( x) = lim [2(x2+2xh+h2)-3x-3h+1]-[2x2-3x+1] h -0 fil x = lim 2x2+4xh+2h2-3x-3h+1-2x2+3x-1 h-0 h fil x = lim 2h-+4xh-3h h -0 h fix = lim 2h + 4x- 3 h -0 f ( x = 4x - 3 The derivative of the function f(x) = 2x2 - 3x + 1 using First Principles is 4x - 3