Logic Math prob. please take a look

Determine the truth value of each of the following.
sets of positive integers

a) ∀x ∃y (x^2 =y)

b) ∀x ∃y (y^2 =x)

c) ∀x ∃y (x-y=1)

please show work please i need help

a) True. The square of any positive integer is also a positive integer.
b) False. If x=2 then y=sqrt(2) which is not a positive integer.
c) False. If x=1 then y=0 which is technically not a positive integer.

Hope this helps!

Im not sure what those fancy lettrings mean but if they mean x and y are the same then

x^2 = y
(0,0)
(1,1)

not really sure though