Question

write the every positive integer can be of the form 4q+2 where q is an integer

Answer 1

Every positive integer can't be of the form 4q+2 because 4q+2=2(2q+1). hence 4q+2 is an even number....so we can't write odd numbers in the form 4q+2 (when q is an integer). also 2q+1 is an odd number. hence the maximum power of 2 that divides 4q+2 is 1. therefore we can't represent the numbers divisible by 4 in this form.