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Solve the following : (i) |x| = 5 ...

Solve the following :
(i) `|x| = 5`
(ii) `x^2- |x|-2 =0 `

Text Solution

Verified by Experts

(i) |x|= 5 i.e those points on real number line which are at distance five untis from '0' which are - 5 and 5 .Thus `|x|= 5 rArr = pm 5`
(ii) `x^2- |x|- 2 = 0 `
`x^2 -|x|- 2 = 0 `
`rArr (|x| - 2 ) ( |x| + 1 )=0 " " ( therefore x^2 = |x|^2)`
`rArr |x| =2 " " ( therefore |x| + 1 ne 0) `
`rArr x= pm 2`
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