Derivatives and Integrals Of Sine and Cosine

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 Take the Derivative & Integrals Of Sine and Cosine Quickly
 Take the Derivatives GRAPHICALLY
 Another Page
 Calculus Lessons Table of Contents
 Use a Pencil to Take a Derivative or Antiderivative of Sine & Cosine Functions
 Just the Graphs of Sine, Cosine, Sine, Cosine for "Taking a derivative Using a Pencil"
 Proof that D_{x}sin(c) = cos(x)
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This page has a "script" and may be used for notes.
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Visit the Interactive Sketch Pad Material On This Topic
 

Take A Derivative or Antiderivative or Sine and Cosine

See these instructions in action on this sketchpad:
Derivative of the Sine.

 1st: Think of the cosine on the horizontal
 as in the positive x axis
 (because the COSINE is the HORIZONTAL COMPONENT of a vector),
 2nd: Think of the symbol sine on the vertical
 as in the positive y axis
 (because the SINE is the VERTICAL COMPONENT of a vector)
 3rd: Think of and place  sin(x) and  cos(x) in the appropriate spots.

 To Take a first or second or third or fourth ... DERIVATIVE,
 move one or two or three or four ... turns in a CLOCKWISE direction.

 To Take a first or second or third or fourth ... ANTIDERIVATIVE,
 move one or two or three or four ... turns in a COUNTERCLOCKWISE direction.
Take First, Second, Third Derivatives of Sine & Cosine Functions GRAPHICALLY

Use the graphs to takes the derivatives.
To take the first derivative, use a pencil. Use the middle point of a pencil as
a tangent point and point the pencil to the right, the greater x values.
Trace the curve, stating the derivative (slope of the tangent) as you do.
Use the stated derivatives (slopes) to describe the curve which is the
derivative functions.
For example, TAKE THE DERIVATIVE OF THE SINE.
 At zero the curve is increasing at a 45% angle so, the slope is 1.
 In the first quadrant, the function is increasing but at a slower rate, the slope is decreasing.
 At 90°, the curve reaches a relative max, the slope is 0.
 In the second quadrant, the function is still decreasing,
the derivative (slope) is negative.
 At 180°, the function is at a 45° angle, the slope is 1.
 In the third quadrant, the curve continues to decrease, but
not as sharply, the slope is negative but increasing.
 At 270°, the function reaches a relative min, and the slope is 0.
 In the third quadrant, the function increases, the derivative (slope) is positive.
 At 360°, the function still increasing, the slope is 1
and the cycle begins to repeat.
What's the function?
The cosine.
The derivative of the sine is the cosine.
Second Derivative
Two methods for taking the second derivative, the slope of the derivative, are
suggested. EITHER repeat the above method using the cosine as the original function, OR,
use the movement of the pencil point and the sine function to compute the second derivative of the sine, d^{2}[sin(x)]/dx^{2}.

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