Answer:
Ok, first in our series we can see two numbers in the Sigma, one bellow 0, and other above, 4.
This means that the value of k will go from 0 to 4, then all the numbers in the sum are:
(-1/2)^0 + (-1/2)^1 + (-1/2)^2 + (-1/2)^3 + (-1/2)^4
So we have 5 terms in our series.
b) to see the sign in each term, we must solve the powers, remember that:
(-1)^n is -1 if n is odd, and is equal to 1 if n is even, so we have:
(-1/2)^0 + (-1/2)^1 + (-1/2)^2 + (-1/2)^3 + (-1/2)^4
= 1 -1/2 + 1/4 - 1/8 + 1/16.
So the sign in each term of the series alternates.
The anser is 6/8 that what i think
Let x be the number of CDs we buy and y the number of CDs we sell.
Each CD sell for $1.5, then the total of money we earn is $1.5y.
Each CD bought for $5, then the total money spent is $-5x
Add the above values like this:
1.5y-5x
We have $20, add them like this:
1.5y-5x+20
Since we want to have<span> at least $10 left when you leave the store, then
we deduce the equation:
</span>
5x-x=-2-7
4x=-9
x=2/3 or x=-2/3
Since there are 2 answers, it is not one solution.
It’s still 50/50. Flipping coins is purely chance. There isn’t an actual pattern, our brain just create one to make sense of things!