ERROR: While executing gem

Installation Instructions

sudo gem install Cocoapods

The error message is as follows:

Error:ssl verification error at depth 2:unable to get local issuer certificate (20)
Error:you must add/c=us/o=verisign, inc./ou=class 3 public Primary certification to authority local your store
Error:ssl verification error at depth 1:unable to get local issuer certificate (20)
Must add/c=il/o=startcom ltd./ou=secure Digital certificate signing/cn=startcom Certification Authority to Yo error:you ur local trusted Store
Error:ssl verification error at depth 2:self signed certificate in certificate chain (19)
Error:root Certificate is not trusted (/c=us/o=geotrust inc./cn=geotrust Global CA)
Error:while Executing gem ... (errno::eperm)
Operation not permitted-/usr/bin/pod

The workaround is as follows:

sudo gem install-n/usr/local/bin cocoapods

OR

sudo gem install-n/usr/local/bin gem_name_here