Ask Dr. Math

High School Archive

Browse High School Calculus
Stars indicate particularly interesting answers or good places to begin browsing.

Selected answers to common questions:
    Chain rule.
    Maximizing the volume of a box.
    Maximizing the volume of a cylinder.
    Volume of a tank.
    What is a derivative?

---

Inverse of a Multivariate Function [05/30/2002]

Let f:NxN -> N such that f(x,y) = 2^x(2y + 1) - 1 for all natural numbers x, y. Let the inverse of f, g be given by g:N -> NxN. Find the inverse of the function g.

Inverting Functions [07/19/2002]

To find the inverse of a function y=f(x), do I interchange the variables x and y, or do I solve for x in terms of y?

Is Infinity a Number ... in Inversive Geometry? [01/15/2010]

A reader attempts to demonstrate infinity as concretely measurable in an inversive geometric construction. Doctor Tom explains analyzes the argument, weighing the pros and cons of the axioms of non-Euclidean geometries, and going on to expose an apparent paradox.

Is pi Squared Rational or Irrational? [01/07/2011]

Doctor Ali provides a proof by contradiction.

Is the Function Invertible? [09/22/1997]

For the following functions f(x) decide if the function is invertible as a function from R to R...

Iterated Limits [5/25/1996]

I don't know how to do the following problems...

Jerk - Derivative of Acceleration [03/16/2001]

I need a mathematical term that begins with the letter J, its definition, and a high-school-level explanation of the term.

kth Derivative of x^n [03/04/2003]

What is a quick way to find the nth derivative of a function? Example: the 7th derivative of x^8.

LaGrange Error for a Taylor Polynomial [05/28/2000]

How can you find the LaGrange error for a Taylor polynomial?

Lagrange Multipliers [01/08/1998]

I have a problem with Lagrange Multipliers - can you help?

Lagrange Multipliers [01/28/2001]

The temperature of a point(x,y,z) on the unit sphere is given by T(x,y,z)=xy+yz. Using Lagrange multipliers, find the temperature of the hottest point on the sphere.

Lagrange Multipliers and Constraints [11/24/1998]

When using the Lagrange Multiplier method, how do you determine which of the two equations is the constraint?

Laplace Transform [01/25/2001]

What are Laplace transforms, and what are their applications?

Latus Rectum [08/08/2002]

I'm trying to find the definition, an explanation, a formula, or anything that will help me to better understand what latus rectum is.

Learning Differential Equations [7/15/1996]

What resources can I use to learn about differential equations?

Lengthening Shadow [10/13/2003]

A man 6 feet tall walks at 4 miles an hour directly away from a lampost 18 feet tall. Why does his shadow lengthen at a constant rate?

Length of a Cubic Curve [12/10/1997]

I need to calculate the true length of a cubic curve.

Let f(x) = 1 + 1/2 + 1/3 + ... + 1/[(2^n)-1] [05/15/1999]

Which of the following inequalities are correct?

L'Hopital's Rule [4/23/1995]

I can't figure out how to take the limit using L'Hopital's rule on this problem...

L'Hopital's Rule [8/11/1996]

How can I solve the following problem: limit as x-> infinity of x^(1/ x)?

L'Hopital's Rule and Limits [8/7/1995]

Find the limit of [sin 3x / tan (x/3)] as x goes to 0.

Lifting an Object of Changing Mass [7/28/1996]

Suppose you grab the end of a chain that weights 3 lb/ft and lift it straight up off the floor at a constant speed of 2 ft/s: determine the force as a function of height; how much work do you do in lifting the top of the chain 4 feet?

Limit As n Approaches Infinity [9/7/1996]

How do I find the limit (n-> -infin.) of (sqrt(2n^2+1))/(2n-1)?

Limit Intuitions [10/01/1998]

Can you explain the intuition behind the formal definition of a limit? derive the equation of the tangent line of a function at a given point?

Limit of n^2/2^n as n Tends to Infinity [12/05/2002]

Demonstrate that the limit as n tends to infinity of the fraction n^2 / 2^n = 0.

The Limit of Sin(1/x) [10/02/1998]

Why does the sine of 1/x have no limit as x approaches 0?

Limit of x sin(1/x) [04/23/2002]

I assumed from the graph that the function had a limit at x=0 of 0, but since it involves sin(1/0) I can not prove this using the basic trigonometric limits (sin x/x and (1-cos x)/x), L'Hopital's rule, or by rearranging the equation. Can you help?

Limit Problem [7/16/1995]

Find the limit of (x^2 + 2x) / (5x - 5) as x tends to infinity.

A Limit Problem [10/24/1996]

What is the limit of (x^2 -4) / (2x) as x approaches infinity?

Limit Problems [08/08/1998]

What is the limit of (sqrt(2-t) - sqrt(2))/t as t->0?

Limit Proof [7/13/1996]

If lim(An/n) = L and L>0, how do you show that lim(An) = + infinity?

Limit Proofs with L'Hopital's Rule [05/27/1998]

How would you prove the following three limits? ...

Limits Approaching Infinity [02/16/2002]

Is the only way to answer them by memorizing all the general questions you may come across?

Limits - Indeterminate Forms [10/12/1997]

I cannot do a problem where I need to convert into the form 0/0 and then use L'Hopital's Rule...

Limits of Multi-Variable Functions [11/12/2004]

Find the limit, if it exists, or show that the limit doesn't exist: lim (x*y*cos(y))/(3*x^2 + y^2) as (x,y) ==> (0,0).

Limits of Sequences [02/25/2001]

Is the limit of [(1 + 1/sqrt(n))^(1.5n)], as n goes to infinity, e? What is the limit as n goes to infinity of [(1 + a/n)^n], where a is not equal to 0?

Limits of the Natural Logarithm [07/22/1998]

Can you help us find the limit of x (ln x)^n as x goes to infinity, for all n? Do we use L'Hopital's Rule?

Linearity and Concavity [12/07/2003]

Why does a linear function have no concavity?

Line Tangent to an Ellipse [03/29/2003]

Find the equation of the tangent to the ellipse x^2 + y^2 = 76 at each of the given points: (8,2),(-7,3),(1,-5). Write your answers in the form y = mx + b.

Logistic Growth of A Rumor Spreading [04/11/1998]

Assuming logistic growth, find how many people know the rumor after two weeks.

Page: [<prev]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 [next>]