Given expression and differentiation: We are given the expression −7x2y−5 and we need to find dxdφ using implicit differentiation. Since the expression does not explicitly solve for y in terms of x, we differentiate both sides of the equation with respect to x, treating y as a function of x (i.e., y(x)).
Product rule application: Differentiate −7x2y with respect to x. Using the product rule, which states that d(uv)/dx=u(dv/dx)+v(du/dx), we differentiate −7x2 and y separately. The derivative of −7x2 with respect to x is −14x, and the derivative of y with respect to x is x0 since y is a function of x.
Derivative of constant: Applying the product rule, we get −7x2⋅dxdy−14xy as the derivative of −7x2y with respect to x.
Combining derivatives: Differentiate −5 with respect to x. The derivative of a constant is 0, so the derivative of −5 with respect to x is 0.
Equating to find derivative: Combine the derivatives from the previous steps to write the full derivative of the expression −7x2y−5 with respect to x. The full derivative is −7x2⋅dxdy−14xy+0.
Isolating and solving: Since we are looking for dxdφ, and φ represents the expression −7x2y−5, we can equate the derivative to 0 because the expression is not equal to a function of x, but rather a constant (which we can assume to be 0 for the purpose of finding the derivative).So, we have −7x2⋅dxdy−14xy=0.
Simplifying the expression: Solve for dxdy. We isolate dxdy on one side of the equation to find its value.−7x2⋅dxdy=14xydxdy=−7x214xy
Simplifying the expression: Solve for dxdy. We isolate dxdy on one side of the equation to find its value.−7x2⋅dxdy=14xydxdy=−7x214xySimplify the expression for dxdy. We can cancel out a x from the numerator and denominator, and also simplify the constants.dxdy=−7x14ydxdy=−2xy
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