Given that (\(_r^n\)) = \(^nC_r\), simplify (\(^{2x + 1}_{3}\)) - (\(^{2x - 1}_3\)) - 2(\(^x_2\))
The expression given is: (^2x + 13) - (^2x - 13) - 2(^x2)
We can simplify this expression by using the formula (^rn) = ^nCr, which represents the number of ways of choosing r objects from a set of n distinct objects.
First, let's simplify (^2x + 13) using the formula:
(^2x + 13) = ^3C2x+1
This represents the number of ways of choosing (2x + 1) objects from a set of 3 distinct objects. Similarly, we can simplify (^2x - 13) using the formula:
(^2x - 13) = ^3C2x-1
This represents the number of ways of choosing (2x - 1) objects from a set of 3 distinct objects.
Now, substituting these values in the given expression, we get:
(^2x + 13) - (^2x - 13) - 2(^x2) = ^3C2x+1 - ^3C2x-1 - 2(^x2)
Next, we can simplify 2(^x2) using the formula:
2(^x2) = 2^xC2
This represents the number of ways of choosing 2 objects from a set of x distinct objects, multiplied by 2.
Substituting this value in the previous expression, we get:
(^2x + 13) - (^2x - 13) - 2(^x2) = ^3C2x+1 - ^3C2x-1 - 2^xC2
This is the simplified expression, which represents the difference between the number of ways of choosing (2x + 1) objects and (2x - 1) objects from a set of 3 distinct objects, minus twice the number of ways of choosing 2 objects from a set of x distinct objects.