# Find the Equation of the Tangent Plane for the Surface z = ycos(x - y) at (2, 2, 2) | Summary and Q&A

3.0K views
âĒ
October 19, 2022
by
The Math Sorcerer
Find the Equation of the Tangent Plane for the Surface z = ycos(x - y) at (2, 2, 2)

## TL;DR

The video explains how to find the equation of the tangent plane to a surface at a given point.

## Key Insights

• ðĪŠ The equation of a tangent plane to a surface at a given point can be found using the formula z - Z0 = (âf/âX)(X - X0) + (âf/ây)(y - y0).
• ðą The partial derivatives (âf/âX) and (âf/ây) represent the rates of change of f with respect to x and y, respectively.
• ð Finding the partial derivatives may require applying the chain rule and the product rule.
• ðĨ Evaluating the partial derivatives at a specific point allows for the determination of the equation of the tangent plane at that point.
• ðĨ The equation of the tangent plane provides information about the local behavior of the surface at the given point.
• âïļ Tangent planes are useful in various areas of mathematics and physics, such as optimization, differential geometry, and numerical analysis.
• âïļ The formula for the equation of the tangent plane is a fundamental tool in multivariable calculus.

## Transcript

hi in this video we're going to find the equation of the tangent plane to the surface Z equals y times the cosine of x minus y at the point 222 solution first thing we're going to do is write down the formula for the equation of the tangent plane which is z minus Z naught equals and then here it's going to be the partial derivative of f with respec... Read More

### Q: What is the formula for the equation of the tangent plane to a surface at a point?

The formula is z - Z0 = (âf/âX)(X - X0) + (âf/ây)(y - y0), where Z0 is the value of the dependent variable at the given point (X0, y0), and (âf/âX) and (âf/ây) are the partial derivatives of the function f with respect to x and y, respectively.

### Q: How are the partial derivatives calculated?

The partial derivative with respect to x is found by treating y as a constant and differentiating the function f(x,y) with respect to x. The partial derivative with respect to y is found using the product rule, as the function involves a product of two functions that depend on y.

### Q: What is the significance of finding the partial derivatives?

The partial derivatives provide information about the rate of change of the function f with respect to each independent variable. These values help determine the slope of the tangent plane at the given point and allow us to write the equation of the tangent plane.

### Q: How do you evaluate the partial derivatives at a specific point?

To evaluate the partial derivatives at a specific point (X0, y0), substitute the values of X0 and y0 into the partial derivative expressions and simplify the calculations.

## Summary & Key Takeaways

• The video demonstrates how to use the formula for the equation of the tangent plane to find the equation for a specific surface.

• The partial derivatives with respect to x and y are calculated using the chain rule and product rule.

• The values of the partial derivatives are substituted into the formula to find the equation of the tangent plane.