Advertisements
Advertisements
प्रश्न
Find the fourth proportional to:
x3 - y2, x4 + x2y2 + y4, x - y.
उत्तर
Let A be the fourth proportional then
x3 - y2 : x4 + x2y2 + y4 = x - y : A
⇒ `(x^3 - y^3)/(x^4 + x^2y^2 + y^4) = (x - y)/"A"`
⇒ A(x3 - y3) = (x - y)(x4 + x2y2 + y4)
⇒ A = `((x - y)(x^4 + x^2y^2 + y^4))/(x^3 - y^3)`
⇒ A = `((x - y)(x^2 + y^2 + xy)(x^2 + y^2 - xy))/((x - y)(x^2 + xy + y^2)`
⇒ A = x2 + y2 - xy.
APPEARS IN
संबंधित प्रश्न
Find two numbers such that the mean proportional between them is 12 and the third proportional to them is 96.
If `x = (sqrt(a + 3b) + sqrt(a - 3b))/(sqrt(a + 3b) - sqrt(a - 3b))`, prove that: 3bx2 – 2ax + 3b = 0.
If a, b, c and dare in continued proportion, then prove that
ad (c2 + d2) = c3 (b + d)
Find the two numbers such that their mean proprtional is 24 and the third proportinal is 1,536.
Show that the following numbers are in continued proportion:
48, 60, 75
The cost of 4 dozen bananas is Rs 104. How many bananas can be purchased for Rs 6.50?
If `a/c = c/d = c/f` prove that : `(a^2)/(b^2) + (c^2)/(d^2) + (e^2)/(f^2) = "ac"/"bd" + "ce"/"df" + "ae"/"df"`
If a, b, c, d, e are in continued proportion, prove that: a : e = a4 : b4.
There is a number in the box `square` such that `square`, 24, 9, 12 are in proportion. The number in the box is ______.
Write True (T) or False (F) against the following statement:
0.9 : 0.36 : : 10 : 4