Find dydx\frac{d y}{d x}, if yx+xy+xx=aby^{x}+x^{y}+x^{x}=a^{b}.

Answer: dydx=−yxln⁡y+xyyx+xx(ln⁡x+1)yxxy+xyln⁡x\frac{dy}{dx} = - \frac{y^x \ln y + x^y \frac{y}{x} + x^x (\ln x + 1)}{y^x \frac{x}{y} + x^y \ln x}

Step-by-step solution

Step 1: Decompose the equation

The given equation involves a sum of three complex terms, each of which is a function raised to another function. To simplify the differentiation process, we can break down the equation into individual terms. Let u=yxu = y^x, v=xyv = x^y, and w=xxw = x^x. The equation then becomes u+v+w=abu+v+w = a^b.

Step 2: Differentiate each term with respect to x

Since aba^b is a constant (as aa and bb are constants), its derivative with respect to xx is 00. Therefore, we need to find the derivative of each term uu, vv, and ww with respect to xx and sum them up to 00.

Step 3: Calculate dudx\frac{du}{dx}

To differentiate u=yxu = y^x, we take the natural logarithm of both sides: ln⁡u=xln⁡y\ln u = x \ln y. Then, we differentiate implicitly with respect to xx. Using the product rule on the right side, we get 1ududx=ln⁡y+x1ydydx\frac{1}{u} \frac{du}{dx} = \ln y + x \frac{1}{y} \frac{dy}{dx}. Finally, we multiply by uu to solve for dudx\frac{du}{dx}.

Step 4: Calculate dvdx\frac{dv}{dx}

Similarly, for v=xyv = x^y, we take the natural logarithm: ln⁡v=yln⁡x\ln v = y \ln x. Differentiating implicitly with respect to xx gives 1vdvdx=dydxln⁡x+y1x\frac{1}{v} \frac{dv}{dx} = \frac{dy}{dx} \ln x + y \frac{1}{x}. Multiplying by vv yields the expression for dvdx\frac{dv}{dx}.

Step 5: Calculate dwdx\frac{dw}{dx}

For w=xxw = x^x, we take the natural logarithm: ln⁡w=xln⁡x\ln w = x \ln x. Differentiating implicitly with respect to xx gives 1wdwdx=ln⁡x+x1x\frac{1}{w} \frac{dw}{dx} = \ln x + x \frac{1}{x}. Multiplying by ww yields the expression for dwdx\frac{dw}{dx}.

Step 6: Substitute and solve for dydx\frac{dy}{dx}

Now, substitute the expressions for dudx\frac{du}{dx}, dvdx\frac{dv}{dx}, and dwdx\frac{dw}{dx} back into the equation dudx+dvdx+dwdx=0\frac{du}{dx} + \frac{dv}{dx} + \frac{dw}{dx} = 0. Group the terms containing dydx\frac{dy}{dx} on one side and the remaining terms on the other side. Finally, divide to solve for dydx\frac{dy}{dx}.

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