Binomial coefficient of 7th term of the expansion 2 x -3 y 20 is-areA- 19 C 6-20 C 5B- 20 C 6- 19 C 6-19 C 5D- 19 C 6

The correct options are B ^20C_6 C ^19C_6+ ^19C_5Given : (2x 3y)^20 nbsp; T_7=T_6+1= ^20C_6(2x)^14( 3y)^6 ∴ Binomial coefficient of 7^th term = ^20C_6 and ^20 ...

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard IX

Mathematics

Ratio and Proportion

Binomial coef...

Question

Binomial coefficient of $7^{t h}$ term of the expansion $(2 x - 3 y)^{20}$ is/are

^{19} C_{6} +^{20} C_{5}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

^{20} C_{6}

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

^{19} C_{6} +^{19} C_{5}

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

^{19} C_{6}

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct options are
B $^{20} C_{6}$
C $^{19} C_{6} +^{19} C_{5}$
Given : $(2 x - 3 y)^{20}$
$T_{7} = T_{6 + 1} =^{20} C_{6} (2 x)^{14} (- 3 y)^{6}$
$∴$ Binomial coefficient of $7^{t h}$ term $=^{20} C_{6}$
and $^{20} C_{6} =^{19} C_{6} +^{19} C_{5}$
$(∵^{n + 1} C_{r} =^{n} C_{r} +^{n} C_{r - 1})$

Suggest Corrections

Similar questions

Q. In the expansion of

{(a^{2} \sqrt{a} + \frac{\sqrt[3]{a}}{a})}^{n}

the binomial coefficient of 3rd term is 36. The 7th term is :

Q. In the expansion of

{(\sqrt{a} + \frac{1}{\sqrt{(3 a)}})}^{n}

, if the ratio of the binomial coefficient of the

4^{t h}

term to the binomial coefficient of the

3^{r d}

term is

\frac{10}{3}

, the

5^{t h}

term is

Q. The

6^{th}

(from the beginning) term in the expansion of the

{[\sqrt{2^{log (10 - 3^{x})}} + \sqrt[5]{2^{(x - 2) log 3}}]}^{m}

is equal to

21

. It is known that the binomial coefficient of the

2^{nd}, 3^{rd}

and

4^{th}

term in the expansion are in an

A . P .

, then the value of

x

is/are

Q. In the binomial expansion of

{(1 + y)}^{n}

, where

n

is a natural number, the coefficients of the

5^{t h}, 6^{t h}

and

7^{t h}

terms are in A.P, find

n

Q. In the binomial expansion of

{(^{3} \sqrt{2} + \frac{1}{^{3} \sqrt{3}})}^{n}

, the ratio of the

7 t h

terms from the beginning to the

7 t h

terms from the end is

1 : 6

, find

n

Join BYJU'S Learning Program

Explore more

Ratio and Proportion

Standard IX Mathematics

Join BYJU'S Learning Program

Binomial coefficient of 7th term of the expansion (2x−3y)20 is/are

The correct options are B 20C6 C 19C6+ 19C5Given : (2x−3y)20 T7=T6+1= 20C6(2x)14(−3y)6 ∴ Binomial coefficient of 7th term = 20C6 and 20C6= 19C6+ 19C5 (∵ n+1Cr= nCr+ nCr−1)

Binomial coefficient of $7^{t h}$ term of the expansion $(2 x - 3 y)^{20}$ is/are