Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

If y2cos(1x)=a2y^{2}\cos\left(\frac{1}{x}\right)=a^{2}, then find dydx\frac{dy}{dx}

Full solution

Q. If y2cos(1x)=a2y^{2}\cos\left(\frac{1}{x}\right)=a^{2}, then find dydx\frac{dy}{dx}
  1. Differentiate with respect to xx: Differentiate both sides of the equation with respect to xx. We have the equation y2cos(1x)=a2y^{2}\cos\left(\frac{1}{x}\right)=a^{2}. To find dydx\frac{dy}{dx}, we need to differentiate both sides of the equation with respect to xx. Since a2a^{2} is a constant, its derivative is 00.
  2. Apply product rule: Apply the product rule to the left side of the equation.\newlineThe left side of the equation is a product of y2y^{2} and cos(1x)\cos\left(\frac{1}{x}\right). The product rule states that the derivative of a product of two functions is the derivative of the first function times the second function plus the first function times the derivative of the second function.
  3. Differentiate y2y^2: Differentiate y2y^{2} with respect to xx. The derivative of y2y^{2} with respect to xx is 2ydydx2y\frac{dy}{dx}, using the chain rule.
  4. Differentiate cos(1x)\cos(\frac{1}{x}): Differentiate cos(1x)\cos\left(\frac{1}{x}\right) with respect to xx. The derivative of cos(1x)\cos\left(\frac{1}{x}\right) with respect to xx is sin(1x)\sin\left(\frac{1}{x}\right) multiplied by the derivative of 1x\frac{1}{x}, which is 1x2-\frac{1}{x^2}, again using the chain rule.
  5. Write down differentiated equation: Write down the differentiated equation.\newlineAfter applying the product rule and differentiating each part, we get:\newline2ydydxcos(1x)y2sin(1x)(1x2)=02y\frac{dy}{dx} \cos\left(\frac{1}{x}\right) - y^{2} \sin\left(\frac{1}{x}\right) \left(-\frac{1}{x^{2}}\right) = 0
  6. Solve for dydx\frac{dy}{dx}: Solve for dydx\frac{dy}{dx}.\newlineTo solve for dydx\frac{dy}{dx}, we need to isolate it on one side of the equation. We can do this by adding y2sin(1x)(1x2)y^{2} \sin\left(\frac{1}{x}\right) \left(\frac{1}{x^{2}}\right) to both sides and then dividing by 2ycos(1x)2y \cos\left(\frac{1}{x}\right).
  7. Simplify to find dydx\frac{dy}{dx}: Simplify the equation to find dydx\frac{dy}{dx}.
    dydx=y2sin(1x)(1x2)2ycos(1x)\frac{dy}{dx} = \frac{y^{2} \sin\left(\frac{1}{x}\right) \left(\frac{1}{x^{2}}\right)}{2y \cos\left(\frac{1}{x}\right)}
    dydx=ysin(1x)(1x2)2cos(1x)\frac{dy}{dx} = \frac{y \sin\left(\frac{1}{x}\right) \left(\frac{1}{x^{2}}\right)}{2 \cos\left(\frac{1}{x}\right)}

More problems from Sin, cos, and tan of special angles