Special Limits in Calculus

Special limits summary Special trig limits There are two commonly used special Calculus limits involving trig functions. They are: $$lim_{xto 0} frac{sin x}{x} =1$$ and $$lim_{xto 0} frac{cos x – 1}{x} = 0.$$ These limit are necessary for determining the...

Derivatives Cheat Sheet

Derivative Rules Linearity (or the sum rule) The derivative is linear, that is $$frac{d}{dx} Big(C f(x) + g(x) Big) = Cf'(x) + g'(x)$$ The Product and Quotient Rules $$frac{d}{dx} Big(f(x)g(x) Big) = f'(x)g(x) + f(x)g'(x)$$ $$frac{d}{dx} Big(frac{f(x)}{g(x)} Big) =...

Derivatives of Logs

Derivatives of logarithms summary Derivative of $ln x$ The derivative of $ln x$ is$$frac{d}{dx} Big( ln x Big) = frac{1}{x}.$$We can prove this by using the fact that $ln x$ and $e^x$ are inverse functions and using the derivative of $e^x$, which is $e^x$. Therefore...

Derivatives of exponentials

Derivatives of exponentials summary The derivative of $e^x$ The derivative of $e^x$ is $$frac{d}{dx} Big( e^x Big) = e^x.$$ We can prove this by going back to the definition. $$begin{eqnarray} frac{d}{dx} Big( e^x Big) &= lim_{hto 0} frac{e^{x+h}-e^x}{h}\ &...

Integral of 1/x

The antiderivative of 1/x Finding the integral of 1/x Because we can see that $frac{1}{x}$ can be written as $x^{-1}$ we’re always tempted to look at the power rule for integration to determine it’s integral, but we can see right away that this...

Derivatives of Trigonometric Functions

Trig derivatives summary The derivative of sin x The derivative of $sin x$ is $$frac{d}{dx} left( sin x right) = cos x.$$ We can prove this by going back to the definition. $$frac{d}{dx} left( sin x right) = lim_{hto 0} frac{sin (x+h)-sin x}{h}.$$ The first thing we...