Q. A curve is defined by the parametric equations x(t)=3cos(−5t) and y(t)=7sin(−8t). Find dxdy.Answer:
Find dtdx: To find dxdy for parametric equations, we need to find dtdy and dtdx separately and then divide dtdy by dtdx.
Find dtdy: First, we find dtdx. The derivative of x(t)=3cos(−5t) with respect to t is dtdx=−3×−5sin(−5t)=15sin(−5t).
Divide dtdy by dtdx: Next, we find dtdy. The derivative of y(t)=7sin(−8t) with respect to t is dtdy=7⋅−8cos(−8t)=−56cos(−8t).
Simplify the expression: Now we divide dtdy by dtdx to find dxdy. So, dxdy=15sin(−5t)−56cos(−8t).
Simplify the expression: Now we divide dtdy by dtdx to find dxdy. So, dxdy=15sin(−5t)−56cos(−8t).We can simplify the expression by factoring out the negative sign in the numerator and denominator, which gives us dxdy=−15sin(−5t)56cos(−8t).
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