Find dydx\frac{d y}{d x}, if x23+y23=a23x^{\frac{2}{3}}+y^{\frac{2}{3}}=a^{\frac{2}{3}}

Answer: dydx=−(yx)13\frac{dy}{dx} = -\left(\frac{y}{x}\right)^{\frac{1}{3}}

Step-by-step solution

Step 1: Differentiate implicitly

To find dydx\frac{dy}{dx}, we need to differentiate both sides of the given equation with respect to xx. Since yy is a function of xx, we will use the chain rule for the term involving yy. The term a23a^{\frac{2}{3}} is a constant, so its derivative will be zero.

Step 2: Apply power rule and chain rule

Applying the power rule, ddx(xn)=nxn−1\frac{d}{dx}(x^n) = nx^{n-1}, to x23x^{\frac{2}{3}} gives 23x−13\frac{2}{3}x^{-\frac{1}{3}}. For y23y^{\frac{2}{3}}, we use the chain rule, which results in 23y−13dydx\frac{2}{3}y^{-\frac{1}{3}}\frac{dy}{dx}. The derivative of the constant a23a^{\frac{2}{3}} is 00.

Step 3: Simplify the exponents

We simplify the exponents: 23−1=−13\frac{2}{3} - 1 = -\frac{1}{3}. This gives us the simplified form of the differentiated equation.

Step 4: Isolate dydx\frac{dy}{dx} term

To solve for dydx\frac{dy}{dx}, we first move the term not containing dydx\frac{dy}{dx} to the right side of the equation.

Step 5: Solve for dydx\frac{dy}{dx}

Divide both sides by 23y−13\frac{2}{3}y^{-\frac{1}{3}} to solve for dydx\frac{dy}{dx}. We can then simplify the expression using the property a−n=1ana^{-n} = \frac{1}{a^n} and a1n=ana^{\frac{1}{n}} = \sqrt[n]{a}.

More from this chapter

All Continuity and Differentiability solutions →

Solve your own maths question free →