P4 Chapter 2: Parametric Equations
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Parametric vs Cartesian Equations
🖉 A parametric equation is one where each of x, y (z etc.) are expressed in terms of some independent parameter.
Sketching Parametric Curves
t | -3 | -2 | -1 | 0 | 1 | 2 | 3 |
x | 9 | 4 | 1 | 0 | 1 | 4 | 9 |
y | -6 | -4 | -2 | 0 | 2 | 4 | 6 |
Let’s just try a few values for the parameter and see what coordinates we get...
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2 4 6 8
6
4
2
O
-2
-4
-6
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Solving Problems involving Parametric Equations
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Test Your Understanding
C4 Jan 2013
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Exercise 3A
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Converting from Parametric 🡪 Cartesian
We can use substitution or well known identities to convert parametric equations into Cartesian ones.
This involves eliminating the parametric variable and forming a single equation.
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Test Your Understanding
C4 June 2013
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C4 Jan 2011
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which double angle formula would be best here?
Exercise 3B
C4 June 2012 Q6
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Harder!
C4 Jan 2008 Q7
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