Question

What are the missing terms???

Answer 1

Answer:

$x^{4} +18x^{2} +81=(x^{2} )^{2}+2(9)^{2} +(3)^{4} \\x^{4} +18x^{2} +81=(x^{2} +9)^{2}$

Step-by-step explanation:

This is just a perfect square