Which of the following is/are true?
(1) (28−1)867=7p−1, where p is a positive integer
(2) (63+1)563=7q+1,where q is a positive integer
1&2
In the expansion of (28−1)867, except the last term,every term will be a multiple of 28(and 7).So we can write (28−1)867 as
(28−1)867=7p−1
Similarly, (63+1)563 can also be written as
(63+1)563=7q+1