Answer :
(1) The correct option is, (B) [tex](2x+9y)(2x-9y)[/tex]
(2) The correct option is, (B) [tex]9c^3d^2(6d^2+c)[/tex]
Explanation :
As we know that a polynomial is a mathematical expression of more that two algebraic terms, the sum of several terms which contains different powers of same variables.
The given expression is,
[tex]4x^2-81y^2[/tex]
Breaks into simpler terms, we get:
[tex]\Rightarrow (2x)^2-(9y)^2[/tex]
Now applying [tex]a^2-b^2=(a+b)(a-b)[/tex] identity, we get:
[tex]\Rightarrow (2x+9y)(2x-9y)[/tex]
Therefore, the factored form of the expression is, [tex](2x+9y)(2x-9y)[/tex]
The given expression is,
[tex]54c^3d^4+9c^4d^2[/tex]
Now taking common things, we get:
[tex]9c^3d^2(6d^2+c)[/tex]
Therefore, the factor of polynomial is, [tex]9c^3d^2(6d^2+c)[/tex]