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High School Archive

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

Selected answers to common questions:
    Negative exponents.
    Scientific notation.

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Non-integer Powers and Exponents [01/06/1999]

How do you find x^n, where n can be an integer, a fraction, a decimal, or an irrational number?

The N'th Root [07/26/1997]

How can you find the n'th root without a calculator?

Number and Its Square Using All 9 Digits Exactly Once [05/22/1998]

Using multiplication facts to find all the whole numbers for which the number and its square together use exactly nine digits 1, 2, 3, ..., 9 only once.

Number of Ancestors 1000 Years Ago [11/22/1999]

How many living relatives would I have had 1,000 years ago, assuming 25 years per generation?

Number of Roots of Polynomial with Radical [02/05/2002]

Solve this equation:r-9(r^(1/2))+8 = 0.

Numbers Raised to the Negative Power [11/14/2001]

I know that 5^(-N) = 1/5^N. I would like to know why.

Ordering Products, Powers, and Parameters of Trigonometric Functions [10/31/2010]

A student wants to know how to unambiguously interpret strings of trigonometric functions, multiplication, and exponentiation. Doctor Peterson digs into a history book -- as well as another math doctor's conversation -- to illuminate the vagaries of the notation.

Perfect Squares and Inspection [5/23/1995]

If x^1/2 + y =11 and y^1/2 + x = 7, what are x and y?

Perfect Squares and Irrational Numbers [02/13/2002]

Isn't any non-perfect square an irrational number? What is the number 0.49? Its square root is 0.7, which is neither irrational nor an integer.

Pi-th Root of -1 [12/15/2000]

How can you find the pi-th root of -1?

Polynomial Function and Exponential Growth [06/08/1999]

How can I find a polynomial function with integer coefficients that has 3, 2, -4 and -1 as zeroes? What is the population of a colony of bacteria 20 seconds after it is discovered?

Power or Exponent? [10/14/2003]

I always thought that 'power' was just a synonym for 'exponent'. Is that incorrect?

Prime Numbers as the Difference of Two Squares [08/07/2002]

Express the prime numbers 7, 15, and 261 as the difference of two squares.

Proof that Sqrt(3) is Irrational [08/14/1997]

How does one prove that sqrt(3) is irrational? or others? Is there a general algorithm? How about just for primes?

Prove or Disprove that Sqrt(2) and Sqrt(4) are Irrational [6/23/1995]

I have learned the following proof that sqrt(2) is irrational...If you use this proof with sqrt(4) you can proof that sqrt(4) is irrational!!! Where did I go wrong?

Prove that Log A is Irrational [06/14/1998]

Can you help me prove that a common log of a number (not powers of 10) is irrational?

Proving a^x = a^y iff x = y [12/13/2000]

How can I prove that a^x = a^y iff y = x for all real numbers x and y?

Proving e is Irrational [11/19/1997]

My professor suggested using a proof by contradiction, but I don't understand how to do it.

Proving the Square Root of 3 is Irrational [12/7/1995]

I have to prove that the square root of 3 is irrational.... First we must assume that: sqrt 3 = p/q; then I have: 3 = p^2/q^2. Where do I go from there?

The Purpose of Powers [07/30/2002]

I don't understand the purpose of powers, what they do, and how to use them.

Raising Sqrt(2) [10/14/1997]

What is the value of x in the following equation: x^x^x^x^x ... = 2 ?

Rationalizing a Cubic Root Denominator [12/06/1997]

I am trying to rationalize the equation: 1/cubrt(9)-2.

Rationalizing the Denominator [07/20/2001]

Is it true that you must get rid of square roots in the denominator of a fraction?

Resolving Decimal Exponents [03/26/2001]

How can you find 7^.3 or 5^.6 without using a calculator? Is there more than one way of doing this?

Rule of 72 [01/26/1999]

Why does the rule of 72 work? For what interest values does it work best?

Rules of Exponent Manipulation [1/22/1996]

f sub r equals the reciprocal of ...

Rules of Exponents [10/02/1999]

Use the rules of indices to simplify the expression [(16x^2)^(1/4)* (4x^3)^(1/2)/[(27^4)^(1/3)].

Scientific Notation: Adding and Subtracting Exponents [03/21/2002]

How do you add and subtract numbers written in scientific notation form?

Scientific Notation and Engineering Notation [10/10/2001]

Convert 0.000 000 000 000 000 000 000 3 to: a) scientific notation; b) engineering notation.

Shortcut for Computing x^n [07/05/2002]

Is there a shortcut that can be used to compute values like 3^12, without doing 12 separate multiplications?

Show that x = 2 [08/29/2001]

Given that: x=(10+(108)^(1/2))^(1/3)+(10-(108)^(1/2))^(1/3), show that x = 2 without using a calculator.

Significant Figures and Scientific Notation [05/21/1997]

How do you tell how many significant figures a number has?

Simplifying Cube Roots in the Denominator [07/12/2001]

Simplify: the cube root of 3 all over the (cube root of 2) minus the (cube root of 4).

Simplifying Exponential Equations [08/19/2003]

A review question: (3r^-1s^2t^3)^2/27r^3st^-2. I don't even know how to begin.

Simplifying Expressions with Radicals [05/26/1998]

Factoring to simplify square roots in expressions such as 12*sqrt(640)/3*sqrt(5).

Simplifying Radicals [06/18/2001]

In the following: sin(15) = sqrt(2-sqrt(3))/2 = (sqrt(6)-sqrt(2))/4, how do you manipulate sqrt(2-sqrt(3))/2 to obtain (sqrt(6)-sqrt(2))/4?

Simplifying Radicals and Exponents [9/3/1995]

A student asks how to simplify square roots and numbers with exponents.

Simplifying Square Roots [9/5/1995]

Could you help me with this problem? 1/2 *Sqrt{24}

Simplifying the Square Root of a Sum [09/27/2004]

Why is it that sqrt(a + b) does not equal sqrt(a) + sqrt(b)?

Simplifying with Cube Roots [01/22/1997]

Simplify: cube root(3) / [cube root(6) + cube root(3)]

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