2006-10-04 18:49:36 · 5 answers · asked by chalkey 1 in Science & Mathematics ➔ Mathematics
d/dx x/2 - 2x^4 is
1/2 - 8x^3
2006-10-04 18:54:08 · answer #1 · answered by Anonymous · 0⤊ 0⤋
if y= x/2 -2x^4
then dy/dx = 1/2 - 8x^3
2006-10-04 19:21:49 · answer #2 · answered by Nick 3 · 0⤊ 0⤋
you have to use 3 formulae d/dx(u+v) = du/dx+dv/dx ..1
d/dx(cu) = c du/dx ...2
d/dx(x^n) = n x^(n-1)... 3
using the above
d/dx(x/2- 2x^4) = d/dx(x/2) - d/dx(2x^4) using 1)
= 1/2 dx/dx (using 2) - 2 d/dx(x^4) (using 2 again)
= 1/2 - 2*4x^3 (using 3 that is dx/dx = 1 and d/dx(x^4) = 4 x^3)
= 1/2 - 8 x^3 (simplification)
2006-10-04 18:52:28 · answer #3 · answered by Mein Hoon Na 7 · 0⤊ 0⤋
d(x/2-2x^4)dx = (2-2x^4-x(-8x^3))/((2-2x^4)^2 = (2+6x^4)/(2-2x^4)^2 = 2(1+3x^4)/(4(1-x^4)^2) = (1+3x^4)/(2(1-x^4)^2)
2006-10-04 19:02:52 · answer #4 · answered by Helmut 7 · 0⤊ 0⤋
f'(x)=(1/2)-8x^3
(1-16x^3)/2
2006-10-04 18:55:07 · answer #5 · answered by raj 7 · 0⤊ 0⤋