A suitable calculator can row-reduce the augmented matrix.
first number: 3
second number: 1
third number: 8
Explanation:
a)


b) First, we have that

On the other hand,

Therefore, both expressions are equal. This makes sense, because selecting k elements from a group of n is the same than specify which elements you will not select. In order to specify those elements you need to select the n-k elements that will not be selected. Hence, each time you are selecting k from n, you are also selecting n-k from n, and from that reason both combinatorial numbers are equal.
Take the .5 of the 17.5 and convert it to a fractin.
we know .5 is equal to 50% or 1/2
now we have a mixed number

in order to convert it into an improper fraction you need to multiply the whole number by the denominator and then add the numerator all while keeping the denominator constant.

so
Answer:
B
Step-by-step explanation:
(x²+5)½ + (x²+5)³/²
->(x+√5) +(x³+√125)
->(x+√5)+(x³+5√5)
->x+x³+√5+5√5
->2x³+6√5
->2(x³+3√5)