Advertisements
Advertisements
प्रश्न
Given four quantities a, b, c and d are in proportion. Show that: (a – c)b2 : (b – d)cd = (a2 – b2 – ab) : (c2 – d2 – cd)
उत्तर
Let `a/b = c/d = k`
`=>` a = bk and c = dk
L.H.S = `((a - c)b^2)/((b -d)cd)`
= `((bk - dk)b^2)/((b - d)d^2k)`
= `b^2/d^2`
R.H.S = `(a^2 - b^2 - ab)/(c^2 - d^2 - cd)`
= `(b^2k^2 - b^2 - bkb)/(d^2k^2 - d^2 - dkd)`
= `(b^2(k^2 - 1 - k))/(d^2(k^2 - 1 - k))`
= `b^2/d^2`
`=>` L.H.S = R.H.S
Hence proved.
APPEARS IN
संबंधित प्रश्न
Check whether the following numbers are in continued proportion.
2, 4, 8
Check whether the following numbers are in continued proportion.
3, 5, 8
If y is the mean proportional between x and y; show that y(x+z) is the mean p roporti ona I between x2+ y2 and y2+ z2
If `a = (b + c)/(2), c = (a + b)/(2)` and b is mean proportional between a and c, prove that `(1)/a + (1)/c = (1)/b`.
Find the mean proportion of: (a – b) and (a³ – a²b), a> b
The cost of 18 chairs is Rs 22770. How many such chairs can be bought for Rs 10120?
If a, b, c, d are in proportion, then
The shadow of a 3 m long stick is 4m long. At the same time of the day, if the shadow of a flagstaff is 24 m long, how tall is the flagstaff?
Are the following statements true?
99 kg : 45 kg = ₹ 44 : ₹ 20
The mean proportion between `3 + 2sqrt(2)` and `3 - 2sqrt(2)` is ______.