
Calculus
Delta y formula worksheets
Find the symbolic change in y for polynomial, rational, composite and trigonometric functions.
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Compare the exact change on a polynomial or trigonometric curve with the tangent-line differential on an actual reference graph.
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Use the supplied graph and exact function values to find Delta y = f(b) - f(a) and dy = f'(a)(b - a).
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Customize this worksheetEach problem shows the actual curve, its tangent at P, the curve endpoint Q and the tangent endpoint T. The worked key keeps the function values, slope, Delta y and dy exact.
Learning objective
Find Delta y = f(b) - f(a) and dy = f'(a)(b - a), then distinguish the curve endpoint Q from the tangent endpoint T.
Worked example
Delta y = 5/4 and dy = 1.
The actual change is 9/4 - 1 = 5/4. The tangent slope at a is 2, so dy = 2(1/2) = 1.
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Choose 4 problems on one student page or 8 problems on two pages, using polynomial, trigonometric, or both function groups.
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