MULUNGUSHI UNIVERSITY SCHOOL OF SCIENCE, ENGINEERING AND TECHNOLOGY DEPARTMENT OF MATHEMATICS AND SCIENCES MSM 112 - Mathematical Methods II (Binomial Expansion) Tutorial Sheet 1- 2020 ————————————————————————————————————————– 1. Simplify 9 10 9 + + 3 6 2 n giving your answer as a single binomial coefficient of the form . r 2. Find the expansion of (i) (3x − 4y)4 3. Expand (a, b)5 . If a = 4. x− 3 4 1 6 x and b = 14 , find the value (as a fraction) of the fourth term of the expansion. (i) Write down the expansion of (2 + x)4 and (2 − x)4 . (ii) Hence, simplify (2 + x)4 + (2 − x)4 . Use your results to find the exact value of (2 + √ 3)4 + (2 − √ 3)4 5. Determine the value of each of the following correct to five significant figures using the binomial theorem. (i) (0.98)7 6. (ii) (1.003)5 (iii) (2.01)9 13 (i) Determine the sixth term in the expansion of 3x + y3 (ii) Determine the middle term of (2x − 5z)8 (ii) Determine the term independent of x in the expansion of x − 1 15 2x2 20 (iv) Determine the term containing x−12 in the expansion of of 2x3 − x1 7 7. Evaluate the coefficients of x4 and x5 in the expansion of x3 − 3 . Hence, evaluate the coefficient of x5 in the 7 expansion of x3 − 3 (x + 6) 8. The first three terms in the expansion of (1 + x + bx2 )n are 1 + 7x + 14x2 . Find the values of a and b . 9. Find the possible value(s) of x for which the following equation involving binomial coefficients holds: 8 x2 = 8 −4x − 4 10. Expand in ascending powers of x as far as the term in x3 , using the binomial theorem. State in each case the limits of x for which the expansion is valid. q √ 5 1 1−x 1 √5 (ii) (2+x) (iii) (iv) 3 + 2x (v) (iii) (i) (1+x) 5 2 3 1+x 5+x (2x+ x2 ) 1