The sum of last ten coefficients in the expansion of (1+x )¹⁹ wen expanded in the ascending power of x is.......

a)2¹⁸

b)2¹⁹

c)2¹⁸ - ¹⁹C₁₀

d)1/2(2¹⁹ - 1)

a)2¹⁸

19

19co+19c1+.......................19c18+19c19=2

but

19co=19c19,19c1=19c18,............

therefore,

last and first ten co efficients are equal

                                                               19

hence sum of last ten coeffients =2 /2

      18

=2