If `(a-2b-3c+4d)(a+2b+3c+4d) = (a+2b-3c-4d)(a-2b+3c-4d)` then `2ad =`

If (a - 2b - 3c + 4d)/(a + 2b - 3c - 4d) = (a - 2b + 3c - 4d)/(a + 2b + 3c + 4d), show that : 2ad = 3bc .

If (3a + 4b)/(3c + 4d) = (3a-4b)/(3c-4d) , then

a=2b=3c=4d then a:b:c:d is

If (a+b+2c+3d)(a-b-2c+3d)=(a-b+2c-3d)(a+b-2c-3d) , then 2b c is equal to 3/2 (b) (3a)/(2d) (c) 3a d (d) a^2d^2

if (2a+3b+4c+5d)/(2a-3b-4c-5d)=(2a-3b+4c-5d)/(2a-3b-4c+5d) , then show that a,3b,2c and 5d are in proportion.

A library has a copies of one book, b copies each of two books, c copies each of three books, a single copy of d books. The total number of ways in which these books can be arranged in a shelf is equal to a. ((a+2b+3c+d)!)/(a !(b !)^2(c !)^3) b. ((a+2b+3c+d)!)/(a !(2b !)^(c !)^3) c. ((a+b+3c+d)!)/((c !)^3) d. ((a+2b+3c+d)!)/(a !(2b !)^(c !)^)

A library has a copies of one book, b copies each of two books, c copies each of three books, a single copy of d books. The total number of ways in which these books can be arranged in a shelf is equal to a. ((a+2b+3c+d)!)/(a !(b !)^2(c !)^3) b. ((a+2b+3c+d)!)/(a !(2b !)^(c !)^3) c. ((a+b+3c+d)!)/((c !)^3) d. ((a+2b+3c+d)!)/(a !(2b !)^(c !)^)

A library has a copies of one book, b copies each of two books, c copies each of three books, a single copy of d books. The total number of ways in which these books can be arranged in a shelf is equal to a. ((a+2b+3c+d)!)/(a !(b !)^2(c !)^3) b. ((a+2b+3c+d)!)/(a !(2b !)^(c !)^3) c. ((a+b+3c+d)!)/((c !)^3) d. ((a+2b+3c+d)!)/(a !(2b !)^(c !)^)