# Math Help - Legendre symbol

1. ## Legendre symbol

Can't figure out why -(7/3)=-(4/3) Anyone can make it simple for me.

2. Originally Posted by joi
Can't figure out why -(7/3)=-(4/3) Anyone can make it simple for me.

$\binom{7}{3}=\binom{1}{3}=1\,,\,\,\binom{4}{3}= \binom{1}{3}=1$ , when taking $4,7=\!\!\pmod 3$

Tonio

3. Thanks Tonio. Can somebody evaluate (7/79). I keep getting (-1). The answer in the back of the book is 1. Obviously I am making a mistake.

4. I get (7/79) = -(2/7) = -(1/7) = -1
Maybe the answer in the back of the book is wrong?

5. Originally Posted by AmateurStudent
I get (7/79) = -(2/7) = -(1/7) = -1
Maybe the answer in the back of the book is wrong?
I agree