Media and Its Effects
OBJECTIVE QUESTIONS 1. If n > 3, then xyz C0 + (x - 1) (y - 1) (z - 1) C1 + (x - 2) (y - 2) (z - 2) C2 + ..... + (x - n) (y - n) (z - n) Cn equals. 1) xyz 2) nxyz 3) - xyz 4) none of these 2. The total number of dissimilar terms in the expansion of (x1 + x2 + .... + xn)3 is 1) n3 2) 3) 4) 3. The coefficient of x6 in the expansion of (1 + x2 - x3)8 is 1) 80 2) 84 3) 88 4) 92 4. The digit at units place in the number 171995 +111995 - 71995 is 1) 0 2) 1 3) 2 4) 3 5. In n is an odd natural number, then equals 1) 0 2) 1 /n 3) 4) none of these 6. If the second, third, and fourth term in the expansion of (x + a)n are 240, 720, 1080 respectively, then the value of n is 1) 15 2) 20 3) 10 4) 5 7. If nN such that (7 + 4 )n = I + F where I N and 0 < F < 1, then the value of (I+F) (1-F) is 1) an even integer 2) an odd integer 3) depends upon n 4) none of these 8. The sum of coefficients of the polynomial (1 + x - 3x2)2143 1) 0 2) 1 3) 72 4) 22143 9. If n is an even postive integer, then the condition that the greatest term in the expansion of (1+x)n may have the greatest coefficient also is 1) 2) 3) 4) none of these 10. If the rth, (r + 1) th and (r + 2) nd coefficient of (1 + x)n are in AP, then n is a root of the equation. 1) x2 - x(4r + 1) + 4r2 - 2 = 0 2) x2 + x (4r + 1) + 4r2 - 2 = 0 3) x2 + x (4r + 1) + 4r2 + 2 = 0 4) none of these 11. If C0 , C1 , C2 ......... Cn are binomial coefficients in the expansion of (1 + x)n , then the value of C0 - 1) 0 2) 3) 4) 12. If n is an integer greater than unity, then the value of a - nC1 (a - 1) + nC2 (a - 2) - nC3 (a - 3) + .... + (-1)n (a - n) is 1) 0 2) 1 3) n 4) -1 13. If C1 stands for nCr , then the sum of the series [C20 - 2C21 + 3C22 + ....