12/08/13 22:00:49.97 FmJpyxWt0
>>548
df/dx = lim Δx->0 {f(x+Δx)-f(x)}/Δx
d(x^2)/dx = lim Δx->0 {(x+Δx)^2-(x)^2}/Δx
= lim Δx->0 {(x^2 +2xΔx +Δx^2 - x^2)} /Δx
= lim Δx->0 {2x -Δx}
= 2x
12/08/13 22:00:49.97 FmJpyxWt0
>>548
df/dx = lim Δx->0 {f(x+Δx)-f(x)}/Δx
d(x^2)/dx = lim Δx->0 {(x+Δx)^2-(x)^2}/Δx
= lim Δx->0 {(x^2 +2xΔx +Δx^2 - x^2)} /Δx
= lim Δx->0 {2x -Δx}
= 2x