FIND THE DERIVATIVE BY THE LIMIT PROCESS!
f(x) = x³ + x²
f(x) = x³ + x²
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lim h->0 (f(x + h) - f(x)) / (x + h - x)
f(x) =
x^3 + x^2
f(x + h) =
(x + h)^3 + (x + h)^2 =
x^3 + 3x^2 * h + 3x * h^2 + h^3 + x^2 + 2hx + h^2
f(x + h) - f(x) =>
x^3 - x^3 + 3x^2 * h + 3x * h^2 + h^3 + x^2 - x^2 + 2hx + h^2 =>
3x^2 * h + 3x * h^2 + h^3 + 2hx + h^2
Divide that by (x + h - x), which reduces to h. So we're dividing by h
3x^2 + 3xh + h^2 + 2x + h
h goes to 0
3x^2 + 3x * 0 + 0^2 + 2x + 0
3x^2 + 2x
The derivative is 3x^2 + 2x
f(x) =
x^3 + x^2
f(x + h) =
(x + h)^3 + (x + h)^2 =
x^3 + 3x^2 * h + 3x * h^2 + h^3 + x^2 + 2hx + h^2
f(x + h) - f(x) =>
x^3 - x^3 + 3x^2 * h + 3x * h^2 + h^3 + x^2 - x^2 + 2hx + h^2 =>
3x^2 * h + 3x * h^2 + h^3 + 2hx + h^2
Divide that by (x + h - x), which reduces to h. So we're dividing by h
3x^2 + 3xh + h^2 + 2x + h
h goes to 0
3x^2 + 3x * 0 + 0^2 + 2x + 0
3x^2 + 2x
The derivative is 3x^2 + 2x