Question
If x and y are connected parametrically by the equations given in Exercise without eliminating the parameter, Find $\frac{\text{dy}}{\text{dx}}.$
$\text{x}=\cos\theta-\cos2\theta,\text{y}=\sin\theta-\sin2\theta$

Answer

The given equations are $\text{x}=\cos\theta-\cos2\theta\text{ and y}=\sin\theta-\sin2\theta$
Then, $\frac{\text{dx}}{\text{d}\theta}=\frac{\text{d}}{\text{d}\theta}(\cos\theta-\cos2\theta)=\frac{\text{d}}{\text{d}\theta}(\cos\theta)-\frac{\text{d}}{\text{d}\theta}(\cos2\theta)$
$=-\sin\theta-(-2\sin2\theta)=2\sin2\theta-\sin\theta$
$\frac{\text{dy}}{\text{d}\theta}=\frac{\text{d}}{\text{d}\theta}(\sin-\sin2\theta)=\frac{\text{d}}{\text{d}\theta}(\sin\theta)-\frac{\text{d}}{\text{d}\theta}(\sin2\theta)$
$=\cos\theta-2\cos2\theta$
$\therefore\ \frac{\text{dy}}{\text{dx}}=\frac{\Big(\frac{\text{dy}}{\text{d}\theta}\Big)}{\Big(\frac{\text{dx}}{\text{d}\theta}\Big)}=\frac{\cos\theta-2\cos2\theta}{2\sin2\theta-\sin\theta}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Find the angle at which the following vectors are inclined to each of the coordinate axes:
$4\hat{\text{i}}+8\hat{\text{j}}+\hat{\text{k}}$
If $\vec{\text{a}}$ and $\vec{\text{b}}$ are mutually perpendicular unit vectors, write the value of $\big|\vec{\text{a}}+\vec{\text{b}}\big|.$
Find the direction cosines of the line passing through the two points (-2, 4, -5) and (1, 2, 3).
Find the maximum and minimum value, $g(x) = x^3 + 1$
Prove that the vectors $\vec{a}-2 \vec{b}+3 \vec{c}, 2 \vec{a}+3 \vec{b}-4 \vec{c}$ and $-7 \vec{b}+10 \vec{c}$ are collinear.
$A$ is a matrix of order $3\times 4$ and $B$ is a matrix of order $4\times 3,$ find the order of the matrix of $AB.$
If $|\vec{\text{a}}|=2,\big|\vec{\text{b}}\big|=3$ and $\vec{\text{a}}.\vec{\text{b}}=3,$ find the projection of $\vec{\text{b}}$ on $\vec{\text{a}}.$
Evaluate the following:
$\sin\Big(\frac{1}{2}\cos^{-1}\frac{4}{5}\Big)$
A small firm manufactures necklaces and bracelets. The total number of necklaces and bracelets that it can handle per day is at most 24. It takes one hour to make a bracelet and half an hour to make a necklace. The maximum number of hours available per day is 16. If the profit on a necklace is ₹ 100 and that on a bracelet is ₹ 300. Formulate on L.P.P. for finding how many of each should be produced daily to maximize the profit? It is being given that at least one of each must be produced.
In a group of 200 items, if the probability of getting a defective item is 0.2, write the mean of the distribution.