Rationalising
Rationalising
Last updated at August 14, 2026 by Teachoo
Transcript
If a = 5 + 2โ6 and b = 1/๐, then what will be the value of ๐^2+๐^2 ? a = 5 + 2โ6 b = 1/๐ = 1/(5 + 2โ6) = 1/(5 + 2โ6) ร (5 โ 2โ6)/(5 โ 2โ6) = (5 โ 2โ6)/(5^2 โ (2โ6)^2 ) = (5 โ 2โ6)/(25 โ 24) We know that ใ(๐+๐)ใ^2 = ๐^2+๐^2+ 2๐๐ ๐^๐+๐^๐ = ใ(๐+๐)ใ^๐ โ ๐๐๐ Here, ๐+๐ = (5+2โ6)+5(5โ2โ6) ๐๐ = (5+2โ6) (5โ2โ6) Thus, ๐^2+๐^2 = ใ(๐+๐)ใ^2 โ 2๐๐ ๐^2+๐^2=ใ10ใ^2โ2 ร 1 =100โ2 =๐๐