3x
= -------------
3y<span>√2
</span>
x
= -------------
y√2
x√2
= -------------
2y
Answer is A. first choice
Differentiate the given solution:

Substitute
and
into the ODE:

and it's easy to see the left side indeed reduces to 0.
Step-by-step explanation:
Given

Hope it will help :)
Yes, substitute a=2.
14 - 4 + 6 - 6 = -2
8 - 10 = -2
The density of the book is 3cm