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Example Question #6 : Exponents And Rational Numbers
Sometimes, seeing rational numbers makes it easier to understand an equation.
Convert the following into a rational number or numbers:
The rule for converting exponents to rational numbers is: .
Even with this, it is easier to work the problem as far as we can with exponents, then switch to rational expression when we run out of room:
At last, we convert, and obtain .
Thus,
.
Example Question #171 : Exponents
What is the sum of the solutions of the equation x2-2x-8=0?
-6
-10
-2
6
2
2
The equation factors to (x-4)(x+2)=0, indicating that the roots are x=-2,4. The sum of these two roots is 2.
Example Question #1 : How To Use Scientific Notation
What is the number 350,000,000 in scientific notation?
3.5 x 106
3.5 x 108
3.5 x 109
3.5 x 107
3.5 x 105
3.5 x 108
350,000,000 = 3.5 x 108 (exponent is equal to the number of decimal points shifted)
Example Question #2 : How To Use Scientific Notation
Given the equation 2xy + 4x² - y = 2x, if x = 2, what does y equal?
0
4
2
-4
-4
We plug in the value given for x and solve for y.
2xy + 4x² - y = 2x
2(2)y + 4(2)² - y = 2(2)
4y + 4(4) - y = 4
4y - y + 16 = 4
3y = -12
y = -4
Example Question #2 : How To Use Scientific Notation
How do you express 657,800 in scientific notation?
65.78 × 104
65.78 × 103
6.578 × 104
6.578 × 103
65.78 × 106
65.78 × 104
657800 = 6.578 × 105
OR
657800 = 65.78 × 104
Exponent on 10 is the number of decimal points over the number has shifted.
Example Question #1 : How To Use Scientific Notation
2 × 100 + 3 × 102 + 4 × 104 = ?
40,302
4,032
40,320
400,032
432
40,302
2 × 100 + 3 × 102 + 4 × 104 =
2 + 300 + 40,000 = 40,302
Example Question #3 : How To Use Scientific Notation
Give this number in scientific notation:
There are six zeros and two more number places, for a total of eight, so 125,000,000 is equivalent to .
Example Question #4 : How To Use Scientific Notation
Simplify the following expression:
Example Question #2 : Other Exponents
What is the number in scientific notation?
The exponent is equal to the number of decimal points shifted.
Example Question #3 : Other Exponents
Convert from scientific to decimal notation:
In this case the exponent is positive hence you have to move the decimal point 4 places to the right from where it is in the problem giving us
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