All it is, is just length times width
Answer:
1320
Step-by-step explanation:
There are three "spots" for balls.
__ __ __
For the first "spot," and without replacement, meaning we don't put the balls back, there are 12 choices.
12 __ __
But for the next spot, there are only 11 choices. And for the next, there are only 10!
12 11 10
Since these are independent events, we multiply them together.
12 x 11 x 10 = 1320
There are 1320 possibilities!
How could we do it on the calculator, much faster? The question says "in order," so we know it's a <em>permutation,</em> not a <em>combination.</em> This is the nPr button on the calculator (math -> prb -> 2). Just type in 12 nPr 3 and you get the same answer, 1320.
The <em><u>correct answers</u></em> are:
3/2 - expansion; 1/4 - contraction; 4 - expansion; 0.8 - contraction; -3 - expansion.
Explanation:
A scale factor larger than 1 would be an expansion. The factors we have listed that are larger than 1 are 3/2 and 4.
A scale factor between 0 and 1 would be a contraction. The factors we have listed that are between 0 and 1 are 0.8 and 1/4.
A negative scale factor will result in a larger, inverted figure. This means the scale factor of -3 will be an expansion.
this is written as
change the greater than or equal to sign to equal to in order to solve it
thus
dividing through by 2
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![\int\limits^{ \frac{\pi}{2} }_0 {sin^{3}(x)} \, dx \\ = \frac{2}{3} \int\limits^{ \frac{\pi}{2} }_0 {sin(x)} \, dx \\ = \dfrac{2}{3}\ [-cos(x)]_0^{\frac{\pi}{2}}=\dfrac{2}{3} \\ ](https://tex.z-dn.net/?f=%5Cint%5Climits%5E%7B%20%5Cfrac%7B%5Cpi%7D%7B2%7D%20%7D_0%20%7Bsin%5E%7B3%7D%28x%29%7D%20%5C%2C%20dx%20%5C%5C%0A%3D%20%5Cfrac%7B2%7D%7B3%7D%20%5Cint%5Climits%5E%7B%20%5Cfrac%7B%5Cpi%7D%7B2%7D%20%7D_0%20%7Bsin%28x%29%7D%20%5C%2C%20dx%20%5C%5C%0A%3D%20%5Cdfrac%7B2%7D%7B3%7D%5C%20%5B-cos%28x%29%5D_0%5E%7B%5Cfrac%7B%5Cpi%7D%7B2%7D%7D%3D%5Cdfrac%7B2%7D%7B3%7D%20%5C%5C%0A%0A%0A%0A%0A)
