- #1
Andrax
- 117
- 0
Homework Statement
we know that |a| < c and |bl < c
prove that : (la+bl + la-bl)/2 < c
The Attempt at a Solution
all I've gotten to so far is this : la+bl < 2c
lal + lbl < 2c
we have : la+bl < lal+lbl
then la+bl < 2c
i need to prove that la-bl < 0.?
also by squaring all i gotten so far is (la+bl + la-bl)/2 < 2c...