Implicit Derivative Evaluator for x² + y² = R²
Enter the coordinates (x, y) of a point on the circle to find the slope of the tangent line (dy/dx) at that point.
Result:
Understanding Implicit Differentiation
Implicit differentiation is a powerful technique in calculus used to find the derivative of a function when it's not explicitly defined as y = f(x). Instead, y is defined implicitly by an equation relating x and y.
When to Use Implicit Differentiation?
You typically use implicit differentiation when it's difficult or impossible to solve an equation for y in terms of x. Common examples include equations of circles, ellipses, or more complex curves where y is intertwined with x.
The Process
- Differentiate Both Sides: Take the derivative of both sides of the equation with respect to x.
- Apply Chain Rule: When differentiating terms involving y, remember to apply the chain rule. For example, the derivative of y² with respect to x is 2y * (dy/dx).
- Isolate dy/dx: After differentiating, rearrange the equation to solve for dy/dx.
Example: The Circle x² + y² = R²
Let's consider the equation of a circle centered at the origin: x² + y² = R², where R is the radius. We want to find dy/dx.
- Differentiate both sides with respect to x:
d/dx(x²) + d/dx(y²) = d/dx(R²) - Apply the power rule and chain rule:
2x + 2y * (dy/dx) = 0(Since R is a constant, R² is also a constant, and its derivative is 0) - Isolate dy/dx:
2y * (dy/dx) = -2xdy/dx = -2x / (2y)dy/dx = -x / y
This formula tells us the slope of the tangent line at any point (x, y) on the circle (as long as y ≠ 0).
How This Calculator Works
This calculator uses the derived formula dy/dx = -x / y for the circle x² + y² = R². You input the x and y coordinates of a point on the circle, and it will compute the value of the derivative at that specific point. Note that if y = 0, the tangent line is vertical, and the derivative is undefined.
Realistic Example:
Consider a circle with equation x² + y² = 25 (so R=5). Let's find the slope of the tangent at the point (3, 4).
- x = 3
- y = 4
- Using the formula
dy/dx = -x / y: dy/dx = -3 / 4 = -0.75
This means at the point (3, 4) on the circle, the tangent line has a slope of -0.75.
Now, try it yourself with the calculator above!