Question

(i) Using Factor theorem find the value of m, if x -3 is a factor of the

polynomial 2x3 - x2 + mx + 18

(ii) Expand (5a + 2b)3 using suitable identity.

Answer 1

Answer:

ans it is 21 and then it is also 21

Answer 2

Answer:

1) f(x)=2x3-x2+mx+18

x-3=0

x=3

by remainder theorem

f(3)=0

2(3)^3-(3)^2+m(3)+18=0

54-9+3m+18=0

63+3m=0

3m= -63

m= -21

2) Formulae:

(a + b)3 = a3 + b3 + 3ab(a + b).

(5a+2b)^3=(5a)^3+(2b)^3+3(5a)(2b)(5a+2b)

=125a^3+8b^3+30ab(5a+2b)

=125a^3+8b^3+150a^2b+60ab^2

Hope it helps you