Question

What is the third term in the binomial expansion of (3x + y3)4?

Answer 1

18x^2*y^6
hope this helps.

Answer 2

Answer:

$18x^2y^6$  that is option third is correct

Explanation:

We have been given with the expression $(3x+y^3)^4$

We have general formula for binomial expansion which is

$a^n +na^{n-1}b+ \frac{(n)(n-1)}{2} a^{n-2}b^2+----------+b^n$

Here $a= 3x , b=y^3and\\n=4$

Substituting the values in the formula we will get

$3x^4+4(3x)^{4-1}y^3+ \frac{(4)(4-1)}{2} 3x^{4-2} (y^{3})^2\\\\ (3x)^4+4(3x)^3y^3+6(3x)^2y^6\\\\(3x)^4+12x^3y^3+18x^2y^6$+----

we can clearly  see that third term of the expansion will be

$18x^2y^6$

Therefore, Option third is correct