Simple applications of the binomial theorem - Question Bank

1. The expansion of (x + y)^n can be used to approximate values like:
A) sqrt(2)
B) log(10)
C) sin(30 degrees)
D) cos(60 degrees)
2. What is the value of C(n, 1)?
A) n
B) 1
C) 0
D) n^2
3. If the expansion of (x + a)^n contains a term with x^k, then the term is given by:
A) nCk * a^(n-k) * x^k
B) nCk * a^k * x^(n-k)
C) nCk * x^k * a^k
D) nCk * x^(n-k) * a^(n-k)
4. What is the coefficient of x^4y^2 in the expansion of (x + y)^6?
A) 15
B) 6
C) 20
D) 10
5. The sum of the binomial coefficients of (x+y)^n is equivalent to the expansion of:
A) (1+1)^n
B) (1-1)^n
C) (0+1)^n
D) (0-1)^n
6. Find the term independent of x in the expansion of (2x - 3/x^2)^9.
A) There is no independent term
B) C(9, 3) * 2^6 * (-3)^3
C) C(9, 6) * 2^3 * (-3)^6
D) C(9, 3) * 2^3 * (-3)^6
7. What is the value of C(5, 2)?
A) 10
B) 5
C) 20
D) 2
8. The expansion of (x + y)^n is symmetric with respect to x and y if:
A) n is even
B) n is odd
C) The coefficients are equal
D) The powers of x and y are equal in each term
9. What is the coefficient of the second term in the expansion of (a + b)^5?
A) 5
B) 1
C) 4
D) 10
10. The general term in the expansion of (x + iy)^n is given by:
A) nCr * x^(n-r) * (iy)^r
B) nCr * x^r * (iy)^(n-r)
C) nPr * x^(n-r) * (iy)^r
D) nPr * x^r * (iy)^(n-r)
11. What is the value of (10)^4?
A) 10000
B) 1000
C) 40
D) 100
12. Find the coefficient of x^2 in (x + y + z)^3.
A) 3
B) 6
C) 1
D) 0
13. What is the sign of the middle term in the expansion of (x - y)^10?
A) Positive
B) Negative
C) Alternating
D) Zero
14. The sum of the coefficients of the terms with even powers of x in the expansion of (1 + x)^n is:
A) 0
B) 2^n
C) 2^(n-1)
D) 1
15. What is the sum of the coefficients of the terms with odd powers of x in the expansion of (1 + x)^n?
A) 0
B) 2^n
C) 2^(n-1)
D) 1
16. Find the term containing x^3 in the expansion of (x + 2)^5.
A) 10x^3
B) 80x^3
C) 40x^3
D) 20x^3
17. What is the coefficient of x^4 in the expansion of (2 - x)^7?
A) C(7, 4) * 2^3 * (-1)^4
B) C(7, 4) * 2^4 * (-1)^3
C) C(7, 3) * 2^4 * (-1)^3
D) C(7, 3) * 2^3 * (-1)^4
18. The value of C(n, r) is equal to C(n, n-r). This property is known as:
A) Symmetry
B) Reciprocity
C) Alternating property
D) Binomial identity
19. What is the coefficient of x^7 in the expansion of (x + 1/x)^15?
A) C(15, 7)
B) C(15, 8)
C) 0
D) C(15, 6)
20. The expansion of (1 + x)^n is valid for:
A) Any real value of x
B) x < 1
C) x > 1
D) x = 1
21. Which term in the expansion of (a + b)^12 is the middle term?
A) The 6th term
B) The 7th term
C) The 13th term
D) The 5th term
22. What is the coefficient of x^r in the expansion of (x + a)^n?
A) nCr * a^(n-r)
B) nCr * a^r
C) nCr * x^r
D) nCr * x^(n-r)
23. The sum of the coefficients in the expansion of (3x - 2y)^3 is:
A) 1
B) -1
C) 0
D) 27
24. What is the value of C(n, 0) + C(n, 1) + C(n, 2) + ... + C(n, n)?
A) 2^n
B) n^2
C) n
D) 1
25. Find the coefficient of the 4th term in the expansion of (x - 2y)^5.
A) 80
B) -80
C) 40
D) -40
26. The expansion of (a + b)^n has how many terms?
A) n
B) n+1
C) n-1
D) 2n
27. What is the coefficient of x^2y^3 in the expansion of (x + y)^5?
A) 10
B) 5
C) 20
D) 15
28. If n is a positive integer, (x + y)^n = Summation from r=0 to n of nCr * x^(n-r) * y^r. The term where r = 0 corresponds to:
A) x^n
B) y^n
C) nCx^n
D) nCy^n
29. What is the coefficient of x^5 in the expansion of (x + 3)^8?
A) 56 * 3^3
B) 56 * 3^5
C) 8C5 * 3^5
D) 8C5 * 3^3
30. The expansion of (a - b)^n is an alternating series if:
A) a and b are positive
B) a is positive and b is negative
C) a is negative and b is positive
D) a and b are negative
31. What is the numerical value of C(10, 3)?
A) 120
B) 360
C) 210
D) 100
32. Find the term independent of x in the expansion of (x^2 - 3/x)^6.
A) 405
B) -405
C) 135
D) -135
33. What is the sum of the coefficients of the expansion of (2x - 3y)^4?
A) 1
B) -1
C) 16
D) -16
34. In the expansion of (x + a)^n, the (r)th term is given by:
A) nCr-1 * x^(n-r+1) * a^(r-1)
B) nCr * x^(n-r) * a^r
C) nCr-1 * x^(n-r) * a^(r-1)
D) nCr+1 * x^(n-r-1) * a^(r+1)
35. If the coefficient of the (r)th term in the expansion of (1 + x)^n is equal to the coefficient of the (r+1)th term, then:
A) n = 2r - 1
B) n = 2r + 1
C) n = r
D) n = r + 1
36. The sum of the binomial coefficients of (a + b)^n is equal to:
A) (a+b)^n
B) 2^n
C) a^n + b^n
D) 1
37. Using the binomial theorem, what is the value of 99^3?
A) 970299
B) 970300
C) 970298
D) 970301
38. What is the value of (1.01)^5 approximated to three decimal places?
A) 1.051
B) 1.050
C) 1.052
D) 1.053
39. Find the constant term in the expansion of (x - 1/x)^6.
A) 20
B) -20
C) 15
D) -15
40. What is the coefficient of x^3 in the expansion of (3 + 2x)^5?
A) 720
B) 1080
C) 240
D) 360
41. Which term in the expansion of (2x - 3y)^7 contains x^4?
A) The 4th term
B) The 5th term
C) The 3rd term
D) The 6th term
42. The coefficient of x^r in the binomial expansion of (1 + x)^n is given by:
A) nCr
B) nPr
C) C(n, r+1)
D) P(n, r-1)
43. In the expansion of (x + y)^9, what is the position of the middle term?
A) 5th term
B) 6th term
C) 4th term
D) 10th term
44. For the expansion of (x + y)^n, when n is even, how many terms are there and what is the position of the middle term?
A) n+1 terms, (n/2 + 1)th term
B) n terms, (n/2)th term
C) n+1 terms, (n/2)th term
D) n terms, (n/2 + 1)th term
45. What is the value of the middle term in the expansion of (x + y)^10?
A) The 5th term
B) The 6th term
C) The 11th term
D) There is no single middle term
46. The expansion of (1 - x)^n is:
A) 1 - nx + (n(n-1)/2!)x^2 - ...
B) 1 + nx + (n(n-1)/2!)x^2 + ...
C) 1 - nx - (n(n-1)/2!)x^2 - ...
D) 1 + nx - (n(n-1)/2!)x^2 + ...
47. The binomial expansion of (1 + x)^n is given by:
A) 1 + nx + (n(n-1)/2!)x^2 + ...
B) 1 - nx + (n(n-1)/2!)x^2 - ...
C) x + nx^2 + (n(n-1)/2!)x^3 + ...
D) 1 + nx + (n(n+1)/2!)x^2 + ...
48. To find the sum of coefficients in (ax + by)^n, we substitute:
A) x = 1, y = 1
B) x = 0, y = 0
C) x = 1, y = 0
D) x = 0, y = 1
49. What is the sum of the coefficients in the binomial expansion of (x + y)^n?
A) 2^n
B) n^2
C) n
D) 1
50. In the expansion of (x + y)^n, what is the (r+1)th term?
A) nCr * x^(n-r) * y^r
B) nCr * x^r * y^(n-r)
C) nPr * x^(n-r) * y^r
D) nPr * x^r * y^(n-r)