Check sibling questions

Ex 5.1, 11 - Find multiplicative inverse of 4 - 3i - Ex 5.1

Ex 5.1, 11 - Chapter 5 Class 11 Complex Numbers - Part 2

This video is only available for Teachoo black users

Solve all your doubts with Teachoo Black (new monthly pack available now!)


Transcript

Ex5.1, 11 Find the multiplicative inverse of the Complex number 4 – 3𝑖 Multiplicative inverse of z = z – 1 Multiplicative inverse of z = 1/𝑧 Putting z = 4 – 3i multiplicative inverse of 4 – 3i = 1/(4 −3 𝑖) Rationalizing = 1/(4 −3𝑖) ×(4 + 3𝑖)/(4 + 3𝑖) = (4+3i)/(4 −3i)(4 + 3𝑖) Using (a – b ) ( a + b ) = a 2 – b 2 = (4 + 3𝑖)/((4)2−(3𝑖)2) = (4 + 3i)/(16 − 9𝑖2) Putting i 2 = − 1 = (4 + 3𝑖)/(16 −9 (−1) ) = (4 + 3𝑖)/(16 + 9) = (4 + 3𝑖)/25 = 4/25+3/25 𝑖

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.