allow checksol to test an expression's equality to zero
allow checksol to test an expression's equality to zero

Arafatk/sympy,maniteja123/sympy,debugger22/sympy,atsao72/sympy,skidzo/sympy,MridulS/sympy,liangjiaxing/sympy,jerli/sympy,cswiercz/sympy,liangjiaxing/sympy,atsao72/sympy,Titan-C/sympy,mcdaniel67/sympy,Vishluck/sympy,kaushik94/sympy,saurabhjn76/sympy,jaimahajan1997/sympy,VaibhavAgarwalVA/sympy,skidzo/sympy,Vishluck/sympy,hrashk/sympy,pbrady/sympy,Gadal/sympy,AkademieOlympia/sympy,Mitchkoens/sympy,sampadsaha5/sympy,shipci/sympy,rahuldan/sympy,mcdaniel67/sympy,shikil/sympy,garvitr/sympy,moble/sympy,Shaswat27/sympy,beni55/sympy,kaichogami/sympy,meghana1995/sympy,wyom/sympy,Sumith1896/sympy,hargup/sympy,Shaswat27/sympy,Designist/sympy,VaibhavAgarwalVA/sympy,drufat/sympy,madan96/sympy,lidavidm/sympy,grevutiu-gabriel/sympy,asm666/sympy,toolforger/sympy,atreyv/sympy,jbbskinny/sympy,abhiii5459/sympy,maniteja123/sympy,kmacinnis/sympy,jerli/sympy,VaibhavAgarwalVA/sympy,toolforger/sympy,jaimahajan1997/sympy,hrashk/sympy,farhaanbukhsh/sympy,Designist/sympy,sahmed95/sympy,yukoba/sympy,ahhda/sympy,dqnykamp/sympy,debugger22/sympy,sampadsaha5/sympy,yashsharan/sympy,AkademieOlympia/sympy,abloomston/sympy,Davidjohnwilson/sympy,MechCoder/sympy,atreyv/sympy,iamutkarshtiwari/sympy,drufat/sympy,bukzor/sympy,ChristinaZografou/sympy,pbrady/sympy,Sumith1896/sympy,ahhda/sympy,postvakje/sympy,Arafatk/sympy,yashsharan/sympy,kaichogami/sympy,mafiya69/sympy,postvakje/sympy,jbbskinny/sympy,kmacinnis/sympy,atreyv/sympy,Mitchkoens/sympy,kmacinnis/sympy,kevalds51/sympy,aktech/sympy,sampadsaha5/sympy,sunny94/temp,kumarkrishna/sympy,souravsingh/sympy,MechCoder/sympy,Davidjohnwilson/sympy,aktech/sympy,postvakje/sympy,lindsayad/sympy,vipulroxx/sympy,dqnykamp/sympy,moble/sympy,shikil/sympy,ga7g08/sympy,madan96/sympy,sunny94/temp,kumarkrishna/sympy,lidavidm/sympy,rahuldan/sympy,lindsayad/sympy,madan96/sympy,pandeyadarsh/sympy,Vishluck/sympy,shipci/sympy,skirpichev/omg,ahhda/sympy,hargup/sympy,cccfran/sympy,saurabhjn76/sympy,jaimahajan1997/sympy,AunShiLord/sympy,shikil/sympy,hargup/sympy,Mitchkoens/sympy,beni55/sympy,sahilshekhawat/sympy,jbbskinny/sympy,cswiercz/sympy,skidzo/sympy,hrashk/sympy,farhaanbukhsh/sympy,cccfran/sympy,Curious72/sympy,asm666/sympy,yukoba/sympy,bukzor/sympy,meghana1995/sympy,oliverlee/sympy,garvitr/sympy,AunShiLord/sympy,grevutiu-gabriel/sympy,sahmed95/sympy,jerli/sympy,wanglongqi/sympy,ga7g08/sympy,sahmed95/sympy,AunShiLord/sympy,wyom/sympy,toolforger/sympy,wyom/sympy,vipulroxx/sympy,pandeyadarsh/sympy,moble/sympy,cccfran/sympy,sahilshekhawat/sympy,Gadal/sympy,AkademieOlympia/sympy,amitjamadagni/sympy,abloomston/sympy,Designist/sympy,diofant/diofant,Curious72/sympy,emon10005/sympy,Curious72/sympy,chaffra/sympy,jamesblunt/sympy,beni55/sympy,oliverlee/sympy,amitjamadagni/sympy,mcdaniel67/sympy,sahilshekhawat/sympy,lindsayad/sympy,kevalds51/sympy,atsao72/sympy,jamesblunt/sympy,MridulS/sympy,abhiii5459/sympy,garvitr/sympy,debugger22/sympy,mafiya69/sympy,meghana1995/sympy,bukzor/sympy,souravsingh/sympy,chaffra/sympy,Shaswat27/sympy,aktech/sympy,kaushik94/sympy,dqnykamp/sympy,oliverlee/sympy,asm666/sympy,MechCoder/sympy,Sumith1896/sympy,yukoba/sympy,wanglongqi/sympy,liangjiaxing/sympy,lidavidm/sympy,abloomston/sympy,rahuldan/sympy,pbrady/sympy,jamesblunt/sympy,saurabhjn76/sympy,Arafatk/sympy,Titan-C/sympy,souravsingh/sympy,kevalds51/sympy,iamutkarshtiwari/sympy,grevutiu-gabriel/sympy,wanglongqi/sympy,sunny94/temp,kaushik94/sympy,kaichogami/sympy,ga7g08/sympy,MridulS/sympy,chaffra/sympy,maniteja123/sympy,Davidjohnwilson/sympy,vipulroxx/sympy,Gadal/sympy,ChristinaZografou/sympy,cswiercz/sympy,Titan-C/sympy,drufat/sympy,abhiii5459/sympy,pandeyadarsh/sympy,ChristinaZografou/sympy,emon10005/sympy,farhaanbukhsh/sympy,yashsharan/sympy,shipci/sympy,mafiya69/sympy,kumarkrishna/sympy,emon10005/sympy,iamutkarshtiwari/sympy