equalTrunc 50 PSE.sqrtExpl (PS.sqrt (\1 -> 1) [1,1])
equalTrunc 500 (1:1:repeat 0) (PS.sqrt (\1 -> 1) (PS.mul [1,1] [1,1]))
checkHoles 50 (PS.sqrt (\1 -> 1)) 1
>>> sqrt 4 2.0
(x :: Area Double) >= _0 ==> sqrt x == nroot pos2 x
sqrt d == nroot 2 d