Find the values of a and b if (7 + 3√5)/(3 + √5) – (7 − 3√5)/(3 − √5)

Find the values of a and b if (7 + 3√5)/(3 + √5) – (7 − 3√5)/(3 − √5) = a+√5  b - Part 2
Find the values of a and b if (7 + 3√5)/(3 + √5) – (7 − 3√5)/(3 − √5) = a+√5  b - Part 3


Transcript

Find the values of 𝑎 and 𝑏 if (7 + 3√5)/(3 + √5) – (7 − 3√5)/(3 − √5) = 𝑎+√5 𝑏 We have (7 + 3√5)/(3 + √5) – (7 − 3√5)/(3 − √5) = ((7 + 3√5))/((3 + √5)) × ((3 − √5))/((3 − √5)) – ((7 − 3√5))/((3 − √5)) × ((3 + √5))/((3 + √5)) = (7(3 − √5) + 3√5(3 − √5))/((3 + √5) (3 − √5)) = ((21 − 7 √5 + 9 √5 − 15))/((3 + √5) (3 − √5)) – ((21 + 7 √5 − 9 √5 − 15))/((3 − √5) (3 + √5)) = ((6 + 2√5))/((9 − 5))−((6 − 2√5))/((9 − 5)) = (6 + 2√5)/4−((6 − 2√5))/4 = (6 + 2√5 − 6 + 2√5)/4 = (4√5)/4 = √5 Comparing with a + √5 b Hence, a = 0 and b = 1

Ask a doubt
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 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.