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Example Questions
Example Question #264 : Exponents
Simplify:
Convert the given expression into a single radical e.g. the expression inside the radical is:
and the cube root of this is :
Example Question #581 : Algebra
Solve for .
Hence must be equal to 2.
Example Question #266 : Exponents
Simplify:
Now
Hence the correct answer is
Example Question #267 : Exponents
Solve for .
If we combine into a single logarithmic function we get:
Solving for we get
.
Example Question #268 : Exponents
If is the complex number such that
, evaluate the following expression:
The powers of i form a sequence that repeats every four terms.
i1 = i
i2 = -1
i3 = -i
i4 = 1
i5 = i
Thus:
i25 = i
i23 = -i
i21 = i
i19= -i
Now we can evalulate the expression.
i25 - i23 + i21 - i19 + i17..... + i
= i + (-1)(-i) + i + (-1)(i) ..... + i
= i + i + i + i + ..... + i
Each term reduces to +i. Since there are 13 terms in the expression, the final result is 13i.
Example Question #1 : How To Use Scientific Notation
Express 0.000000076 in scientific notation.
Write the number:
Counting the number of places, move the decimal point to the right until it is after the first nonzero digit:
The resulting number is 7.6; the number of places the decimal point moved to the right was 8. In scientific notation, this number is .
Example Question #2 : How To Use Scientific Notation
Express the square of in scientific notation.
Take advantage of the exponent rules.
Example Question #3 : How To Use Scientific Notation
The number is equivalent to which of the following?
Each of the answers to this question are in scientific notation. To determine the exponent on the 10, see how many places you need to move the decimal over to get from your original number to 2.79.
Because the decimal place moves 5 places, the exponent will be 5, and because the decimal moves to the RIGHT, the exponent is going to be negative.
So the answer to the quesiton is
Example Question #1 : How To Use Scientific Notation
Put the following value in scientific notation:
Our first value for scientific notation should be between and
. We then multiply this value by
raised to a power equal to the number of spaces our decimal has moved to the left.
Example Question #1 : Algebraic Fractions
Given the expression, , which value CANNOT be equal to
?
cannot equal a value which would make the denominator equal to 0. In order to figure out what that value is, we must first simplify this fraction, then set each factor of the denominator equal to 0. As follows:
First, simplify by finding the original binomial multiples:
Now, set each factor of the denominator equal to 0
If OR
, the denominator will equal 0.
is the only choice provided by the answers.
Note: Even though you can cancel out from the numerator and denominator,
still cannot be equal to two. The graph would have a hole at
and an aymptote at
.
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