# Multiplicative inverse

• February 13th 2006, 04:06 PM
suedenation
Multiplicative inverse
Find the multiplicative inverse of [87] in Z150.

Use this answer to find all x in Z150 so that [87]x = [11].

Thanks guys ;)
• February 14th 2006, 01:53 PM
ThePerfectHacker
Quote:

Originally Posted by suedenation
Find the multiplicative inverse of [87] in Z150.

Use this answer to find all x in Z150 so that [87]x = [11].

Thanks guys ;)

I understand your question as,
Given the ring with unity $\mathbb{Z}_{150}$ find the multiplicative inverse of $87$.
Thus, you need to solve the congruence,
$87x\equiv 1\mod (150)$