Home
Class 10
MATHS
If a : b = c : d, then show that sqrt(a^...

If a : b = c : d, then show that `sqrt(a^(2) + c^(2)) : sqrt(b^(2) + d^(2)) = (pa + qc) : (pb+qd)`

Text Solution

Verified by Experts

Given that ` a : b = c : d rArr a/b = c/d = k (let) [k ne 0]`
`:. ` a = bk and x = dk.
Now, LHS = `sqrt(a^(2)+c^(2)) : sqrt(b^(2) + d^(2)) = sqrt(a^(2) + c^(2))/sqrt(b^(2) + d^(2)) = sqrt((bk)^(2) + (dk)^(2))/sqrt(b^(2) + d^(2))`
`= sqrt(b^(2)k^(2)+d^(2)k^(2))/sqrt(b^(2)+d^(2)) = sqrt(k^(2)(b^(2) + d^(2)))/sqrt(b^(2) + d^(2)) = (ksqrt(b^(2)+d^(2)))/sqrt(b^(2) +d^(2) ) = k`
RHS ` = (pa + qc) : (pb + qd) = (pa+qc)/(pb+qd)`
` = ( xx bk + q xxdk)/(pb + qd) = (k(pb+qd))/((pb+qd)) = k`.
` :. ` LHS = RHS
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • RATIO AND PROPORTION

    CALCUTTA BOOK HOUSE|Exercise EXERCISE - 2.1 (Very Short Answer Type Questions) MCQs|4 Videos
  • RATIO AND PROPORTION

    CALCUTTA BOOK HOUSE|Exercise EXERCISE - 2.1 (True or False)|1 Videos
  • RATIO AND PROPORTION

    CALCUTTA BOOK HOUSE|Exercise EXAMPLES (Fill in the blanks)|3 Videos
  • QUADRATIC SURDS

    CALCUTTA BOOK HOUSE|Exercise Exercise -3.2|28 Videos
  • RECTANGULAR PARALLELOPIPED OR CUBOID

    CALCUTTA BOOK HOUSE|Exercise EXERCISE-(MCQs)|40 Videos

Similar Questions

Explore conceptually related problems

If a : b = c : d , then prove that (a + c) : (b + d) = sqrt(a^(2) - c^(2)) : sqrt(b^(2) - d^(2))

If a/b = b/c = c/d , then prove that (a^(2) + b^(2) + c^(2))(b^(2) + c^(2)+d^(2)) = (ab + bc cd)^(2)

If a : b = c : d , then prove that the - proportional of (a^(2) + c^(2)) " and " (b^(2) + d^(2)) " is " (ab + cd) .

If a/b = c/d ,then show that bd ((a+b)/b + (c+d)/d)^(2) = 4 (a + b) (c + d)

If a, b, c and d are in G.P., show that, (b-c)^(2) + (c-a)^(2)+ (d-b)^(2) = (a-d)^(2) .

If 2x = sqrt((a)/(b)) - sqrt((b)/(a)) , then show that (2a sqrt(1 + x^(2)))/(x + sqrt(1 + x^(2))) = a + b

If a, b, c and d are in G.P., show that, (a-b)^(2), (b-c)^(2), (c-d)^(2) are in G.P.

If a, b, c and d are in G.P., show that, a^(2) + b^(2), b^(2) + c^(2), c^(2) + d^(2) are in G.P.

If a, b, c and d are in G.P. show that (a^2+b^2+c^2)(b^2+c^2+d^2) = (ab+bc+cd)^2

If a,b,c,d be in G.P. show that (b-c)^2 + (c-a)^2 + (d-b)^2 = (a-d)^2 .