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Sets and Functions

Express in tabular method:
 1. { x  N : x2 > 15 and x3 < 225 }    ans: {4, 5, 6}
 2. { x  N : x is prime number and x < 8 }

Prove/Show that
1. 

Evaluate
1. f(1t2)+1f(1t2)1 when f(x) = 5x2+35x23   [dhaka board 2019]

* A = { xN : x is even and x6 } 
  Evaluate P(A). 
  Show that if A has n elements, P(A) has 2n elements.
answer:
   A = { 2, 4, 6 }
   P(A) = { {}, {2}, {4}, {6}, {2, 4}, {2, 6}, {4, 6}, {2, 4, 6} }
   Number of elements in A, n = 3
   Number of elements in P(A) = 8 = 23 = 2n .

problem: Given that B = {5, 7, 11, 13} - Determine P(B) to show that number of elements of P(B) is 2n , where n is the number of elements of B.   (D.B. 2024)

      P(B)={ϕ,{5},{7},{11},{13},{5,7},{5,11},{5,13},{7,11},{7,13},{11,13},{5,7,11},{5,7,13},{5,11,13},{7,11,13},{5,7,11,13}} 

problem: Determine the intersection set of all factors of 35 and 45. (R.B. 2024)

problem: If C={xN:x2>7andx3<136} Express C  in roster method. (Ch.B. 2020)

                       C = {3, 4, 5}

problem: If f(x)=1+x3+x6x3 show that f(x)=f(x2)    (C.B. 2024)

problem: Determine the solution set of y2=5y           (B.B. 2024)

                            solution set = {value1, value2}