Advertisement Remove all ads

if |axb|2+|a.b|2=400 then write the value of |b| - Mathematics

Sum

if `|vecaxxvecb|^2+|veca.vecb|^2=400 ` and `|vec a| = 5` , then write the value of `|vecb|`

Advertisement Remove all ads

Solution

`|vecaxxvecb|^2+|veca.vecb|^2=400 `

 `=>{|veca||vecb|sintheta}^2+{|veca||vecb|costheta}^2=400`

 `=>|veca|^2|vecb|^2sin^2theta+|veca|^2|vecb|^2cos^2theta=400`

`=>|veca|^2|vecb|^2=400`

 `=>25xx|vecb|^2=400`

`=>|vecb|^2=16`

`=>|vecb|=4`

Concept: Vectors Examples and Solutions
  Is there an error in this question or solution?
Advertisement Remove all ads
Advertisement Remove all ads
Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×