Multivariable Calculus · free preview

3.9 Higher Dimensions

How does the idea of a level curve for a function of two variables generalize to functions of three or more variables?

1. Higher Dimensions

Higher Dimensions

2. Introduction

Introduction

3. Inputs and Outputs with Functions of Three or More Variables

Inputs and Outputs with Functions of Three or More Variables

4. Visualizing Functions of Three or More Variables

Visualizing Functions of Three or More Variables

5. Measuring Change with Functions of Three or More Variables

Measuring Change with Functions of Three or More Variables

6. Directional Derivatives and Gradients

Directional Derivatives and Gradients

7. State the equation a…

State the equation and shape of the level curves for the function f(x,y)=x2+y2f(x,y)=x^2+y^2 for the values −2,−1,0,1,2-2,-1,0,1,2.

8. Work through this ex…

Work through this exercise and explain your reasoning step by step.

9. Work through this ex…

Work through this exercise and explain your reasoning step by step.

10. In this activity

In this activity, we will look at level surfaces created by two three-variable functions and consider the direction in which the output is increasing or decreasing as fast as possible.

11. In this activity

In this activity, we will look at level surfaces created by two three-variable functions and consider the direction in which the output is increasing or decreasing as fast as possible.

12. Work through this ex…

Work through this exercise and explain your reasoning step by step.

13. Work through this ex…

Work through this exercise and explain your reasoning step by step.

14. Work through this ex…

Work through this exercise and explain your reasoning step by step.

15. Calculate $\nabla f$…

Calculate ∇f\nabla f and ∇g\nabla g.

16. Sketch the level sur…

Sketch the level surfaces of ff for the values k={−2,−1,0,1,2}k=\{-2,-1,0,1,2\}. Write a few sentences about the shape of each of these level surfaces and describe how the level surfaces change in terms of the value of kk.

17. Write a few sentence…

Write a few sentences about how the direction and magnitude of ∇f\nabla f is related to the level surfaces from the previous part.

18. Sketch the level sur…

Sketch the level surfaces of gg for the values k={−2,−1,0,1,2}k=\{-2,-1,0,1,2\}. Write a few sentences about the shape of each of these level surfaces and describe how the level surfaces change in terms of the value of kk. You may find it helpful to notice that each of the level surfaces can be expressed with zz as a function of xx and yy.

19. Write a few sentence…

Write a few sentences about how the direction and magnitude of ∇g\nabla g is related to the level surfaces from the previous part.

20. Find the equation of…

Find the equation of the tangent plane to the surface given by xz+2x2y+y2z3=11xz+2x^2y+y^2z^3=11 at the point (2,1,1)(2,1,1).

21. Suppose that $\nabla…$

Suppose that ∇fP=⟨2,−4,4⟩\nabla f_P =\langle 2,-4,4\rangle. Is ff increasing or decreasing at PP in the direction ⟨2,1,3⟩\langle2,1,3\rangle?

Practice this interactively

Free account · instant grading · spaced review that schedules itself.

Start this course — free