B) {x|x ∈ U and 2x is prime}
x is greater than 1.
the only even prime number is 2
2 times anything is even.
the minimum x value is 2. 2x is 4, therefore higher than the only even number
every value 2x will have a multiple of 2 so it will not be prime.


This is a way to factoring trinomials (there exist different equivalent methods).
Multiply the trinomial but the term accompanying
. This is the second line. Then, you could take the square of the
, ant try to create a factor () () that will correspond to the expression in the second line. That is, we want 
In ? we put the corresponding numbers that, if we multiply them we will obtain 42, and if we add them we will obtain 13. This numbers are 6 and 7. Then, we have 
The last step is divide by the number that we multipy in the first step.
Answer:
We have expanded formula of (-4x-1)² = a²+2ab+b².
So, we write the formula in square form as (a+b)².
Since we have a²-b² in step 4. We further write this as (a+b)(a-b). This is the factor formula of a²-b².
As we had two terms in place of in (a+b)(a-b), we multiply the term 'b' with '+' and '-' sign respectively.
Write the second expression given in the question.
Write the terms in the form of cube.
Write the factor formula of a³-b³) in the form of (a-b)(a²+ab+b²).
Write the H.C.F. (Highest Common Factor) of the given expressions by analysing the factors you generated in each expressions. Here, (4x²+2x+1) are the common factors.
Answer: $244.55
A = $250 ; r=0.002 t= 11 [From 2007 to 2018 , t=2018-2007]
Max value of x is infinite and min value of x is 0