English

If ab=cd=cf, prove that each ratio is 3a2-5c2+7e23b2-5d2+7f2 - Mathematics

Advertisements
Advertisements

Question

If `a/b = c/d = c/f`, prove that each ratio is `sqrt((3a^2 - 5c^2 + 7e^2)/(3b^2 - 5d^2 + 7f^2)`

Sum

Solution

`a/b = c/d = c/f` = k(say)
∴ a = k, c = dk, e = fk
`sqrt((3a^2 - 5c^2 + 7e^2)/(3b^2 - 5d^2 + 7f^2)`

= `sqrt((3b^2k^2 - 5d^2k^2 + 7f^2k^2)/(3b^2 - 5d^2 - 7f^2)`

= k`sqrt((3b^2 - 5d^2 + 7f^2)/(3b^2 - 5d^2 + 7f^2)` = k
Hence proved.

shaalaa.com
  Is there an error in this question or solution?
Chapter 7: Ratio and Proportion - Chapter Test

APPEARS IN

ML Aggarwal Understanding ICSE Mathematics [English] Class 10
Chapter 7 Ratio and Proportion
Chapter Test | Q 13.1
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×