How do i find dy/dx in terms of t for two parametric equations that are in terms of t.
To differentiate parametric equations we have to use the chain rule in a special way.
We know that the chain rule can be written as dy/dx = dy/dt * dt/dx, as both dts cancel. But if we have an equation x in terms of t, and an equation y in terms of t, the above equation will no longer work, as we want dy/dt, but also dx/dt (rather than dt/dx).
To manage this the trick we use is simply to rewrite the equation as dy/dx = dy/dt / dx/dt. Using this we can now differentiate both equation y and equation x like normal, then put them as a fraction with dy/dt on top and dx/dt on the bottom and reduce this fraction to its simplest form.
BW
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