Final answer:
To grep for numbers ending in 1-5 in a file, use the command 'grep '[1-5]$' filename', where '[1-5]$' is the regex pattern that matches any line ending with a digit from 1 to 5.
Step-by-step explanation:
To grep an expression ending with the numbers 1 to 5, you can use regular expressions (regex) within the grep command. Assuming 'voyager credit card' is a file containing various credit card numbers, here is how you would grep for numbers ending in 1-5:
grep '[1-5]$' voyager_credit_card.txt
This command will search through the file voyager_credit_card.txt and print out all lines where the ending character is a number from 1 to 5. The regex pattern '[1-5]$' specifies that the line should end ($ is the end-of-line anchor) with a digit in the range 1 to 5.