Order does not matter so use "n choose k" formula is used to find number of unique combinations.
c=n!/(k!(n-k)!) where n is total possible choices and k is number of selections.
c=4!/(2!(4-2)!)
c=4!/(2!2!)
c=24/(2*2)
c=24/4
c=6
So there are 6 different two topping options when there are four different toppings to choose from.
Answer:
None of the pairs of expressions are equal
Step-by-step explanation:
• 2n ≠ 2 +n
2n is the same as 2 times of n (expressed as a multiplication sign), while 2 +n is the addition of 2 to n.
•n² ≠ 2n
n²= n ×n
2n= 2 ×n
• 2n² ≠ (2n)²
Note that in the latter, there is a bracket which means that the square applies to both 2 and n.
(2n)²
= (2)² × n²
= (2 ×2)(n²)
= 4n²
Thus, none of the pairs of expressions are equal.
