bila f(x)=2xpangkat3-3xpangkat2+x-10 maka f'(x)=
Pertanyaan
1 Jawaban
-
1. Jawaban dyhan5241
f(x) = 2x^3 – 3x^2 + x – 10
f(x+h) = 2(x^3 + x^2 h + 2x^2 h + 2xh^2 + xh^2 + h^3) – 3(x^2 + 2xh + h^2) + (x + h) – 10
= 2x^3 + 2x^2 h + 4x^2 h + 4xh^2 + 2xh^2 + 2h^3 - (3x^2 + 6xh + 3h^2) + (x + h) – 10
= 2x^3 + 2x^2 h + 4x^2 h + 4xh^2 + 2xh^2 + 2h^3 - 3x^2 - 6xh - 3h^2 + x + h – 10
F’(x) = lim(h>0) f(x+h) - f(x) / h
= lim(h>0) (2x^3 + 2x^2 h + 4x^2 h + 4xh^2 + 2xh^2 + 2h^3 - 3x^2 - 6xh - 3h^2 + x + h – 10) – (2x^3 – 3x^2 + x – 10) / h
= lim(h>0) 2x^3 + 2x^2 h + 4x^2 h + 4xh^2 + 2xh^2 + 2h^3 - 3x^2 - 6xh - 3h^2 + x + h – 10 – 2x^3 + 3x^2 - x + 10 / h
= lim(h>0) 2x^2 h + 4x^2 h + 4xh^2 + 2xh^2 + 2h^3 - 6xh - 3h^2 + h / h (selanjutnya pisahkan h nya)
= lim(h>0) h(2x^2 + 4x^2 + 4xh + 2xh + 2h^2 - 6x - 3h + 1) / h (h dan h di coret)
= lim(h>0) 2x^2 + 4x^2 + 4xh + 2xh + 2h^2 - 6x - 3h + 1
= lim(h>0) 6x^2 + 6xh + 2h^2 - 6x – 3h + 1 (lalu subsitusi nilai h = 0)
= lim(h>0) 6x^2 + 6x(0) + 2(0)2 – 6x – 3(0) + 1
= lim(h>0) 6x^2 + 0 + 0 – 6x – 0 + 1
= 6x^2 – 6x + 1.
Selesai, kalau misalnya salah saya mohon maaf.