bash how to remove the first n lines of a file

C++
# Example usage (3 options):
tail -n +43 input_file	# Print from the 43rd line on
sed 1,42d input_file	# Print from the 43rd line on
sed -i 1,42d input_file	# Remove the first 42 lines in place (meaning 
	# that the file is changed without having to print the output to a 
    # new file)
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