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The differentiable functions xx and yy are related by the following equation: sin(x)+cos(y)=2\sin(x) + \cos(y) = \sqrt{2}. Also, dxdt=5\frac{dx}{dt} = 5. Find dydt\frac{dy}{dt} when y=π4y = \frac{\pi}{4} and 00.

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Q. The differentiable functions xx and yy are related by the following equation: sin(x)+cos(y)=2\sin(x) + \cos(y) = \sqrt{2}. Also, dxdt=5\frac{dx}{dt} = 5. Find dydt\frac{dy}{dt} when y=π4y = \frac{\pi}{4} and 00.
  1. Given Equation and Derivative: We are given the equation sin(x)+cos(y)=2\sin(x) + \cos(y) = \sqrt{2} and the derivative dxdt=5\frac{dx}{dt} = 5. We need to find dydt\frac{dy}{dt} when y=π4y = \frac{\pi}{4} and x=0x = 0. To do this, we will differentiate both sides of the given equation with respect to tt using the chain rule.
  2. Differentiating sin(x)\sin(x): Differentiating sin(x)\sin(x) with respect to tt gives us cos(x)(dxdt)\cos(x) \cdot \left(\frac{dx}{dt}\right) because the derivative of sin(x)\sin(x) with respect to xx is cos(x)\cos(x) and then we multiply by dxdt\frac{dx}{dt} due to the chain rule.
  3. Differentiating cos(y)\cos(y): Differentiating cos(y)\cos(y) with respect to tt gives us sin(y)(dydt)-\sin(y) \cdot \left(\frac{dy}{dt}\right) because the derivative of cos(y)\cos(y) with respect to yy is sin(y)-\sin(y) and then we multiply by dydt\frac{dy}{dt} due to the chain rule.
  4. Differentiating constant: Now we differentiate 2\sqrt{2} with respect to tt, which is a constant, so its derivative is 00.
  5. Derivative Equation: Putting it all together, we get the following equation from the derivatives: cos(x)dxdtsin(y)dydt=0\cos(x) \cdot \frac{dx}{dt} - \sin(y) \cdot \frac{dy}{dt} = 0
  6. Substitute Values: We substitute the given values into the differentiated equation: x=0x = 0, y=π4y = \frac{\pi}{4}, and dxdt=5\frac{dx}{dt} = 5. This gives us:\newlinecos(0)5sin(π4)(dydt)=0\cos(0) \cdot 5 - \sin\left(\frac{\pi}{4}\right) \cdot \left(\frac{dy}{dt}\right) = 0
  7. Solve for dy/dt: We know that cos(0)=1\cos(0) = 1 and sin(π4)=22\sin(\frac{\pi}{4}) = \frac{\sqrt{2}}{2}. Substituting these values into the equation gives us:\newline1×5(22)×(dydt)=01 \times 5 - (\frac{\sqrt{2}}{2}) \times (\frac{dy}{dt}) = 0
  8. Rearrange Equation: Solving for dy/dtdy/dt, we get:\newline5(2/2)(dy/dt)=05 - (\sqrt{2}/2) \cdot (dy/dt) = 0
  9. Isolate dydt\frac{dy}{dt}: Rearrange the equation to solve for dydt\frac{dy}{dt}:(22)(dydt)=5\left(\frac{\sqrt{2}}{2}\right) \cdot \left(\frac{dy}{dt}\right) = 5
  10. Simplify Equation: Divide both sides by 2/2\sqrt{2}/2 to isolate dydt\frac{dy}{dt}:\newlinedydt=5(2/2)\frac{dy}{dt} = \frac{5}{(\sqrt{2}/2)}
  11. Rationalize Denominator: Simplify the right side of the equation: dydt=5×(22)\frac{dy}{dt} = 5 \times \left(\frac{2}{\sqrt{2}}\right)
  12. Final Simplification: Simplify further by multiplying 55 by 22\frac{2}{\sqrt{2}}:dydt=102\frac{dy}{dt} = \frac{10}{\sqrt{2}}
  13. Final Simplification: Simplify further by multiplying 55 by 22\frac{2}{\sqrt{2}}:
    dydt=102\frac{dy}{dt} = \frac{10}{\sqrt{2}}To rationalize the denominator, multiply the numerator and the denominator by 2\sqrt{2}:
    dydt=(102)(22)\frac{dy}{dt} = \left(\frac{10}{\sqrt{2}}\right) * \left(\frac{\sqrt{2}}{\sqrt{2}}\right)
  14. Final Simplification: Simplify further by multiplying 55 by 22\frac{2}{\sqrt{2}}:
    dydt=102\frac{dy}{dt} = \frac{10}{\sqrt{2}}To rationalize the denominator, multiply the numerator and the denominator by 2\sqrt{2}:
    dydt=(102)(22)\frac{dy}{dt} = \left(\frac{10}{\sqrt{2}}\right) * \left(\frac{\sqrt{2}}{\sqrt{2}}\right)Simplify the expression:
    dydt=1022\frac{dy}{dt} = \frac{10\sqrt{2}}{2}
  15. Final Simplification: Simplify further by multiplying 55 by 22\frac{2}{\sqrt{2}}:
    dydt=102\frac{dy}{dt} = \frac{10}{\sqrt{2}}To rationalize the denominator, multiply the numerator and the denominator by 2\sqrt{2}:
    dydt=(102)(22)\frac{dy}{dt} = \left(\frac{10}{\sqrt{2}}\right) * \left(\frac{\sqrt{2}}{\sqrt{2}}\right)Simplify the expression:
    dydt=1022\frac{dy}{dt} = \frac{10\sqrt{2}}{2}Finally, we can simplify 1022\frac{10\sqrt{2}}{2} to 525\sqrt{2}:
    dydt=52\frac{dy}{dt} = 5\sqrt{2}

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