4th term in (x - 2y)12 = T4 = T3 + 1 = 12C3(x)12 - 3(-2y)3 [Tr + 1 in (a + b)n = nCr an – r br] = 12C3(x)9 (-2)3 (y)3 = = -1760 x9 y3

Q. 195.0( 2 Votes )

Find the

Class 11th

Answer :

4th term in (x - 2y)¹² = T₄ = T₃ _{+ 1}
                              = ¹²C₃(x)^{12 -} ³(-2y)³
     [T_{r + 1} in (a + b)ⁿ = ⁿC_r a^{n – r} b^r]
                              = ¹²C₃(x)⁹(-2)³ (y)³
                              =