Question

Let `aa n db` be the roots of the equation `x^2-10 c x-11 d=0` and those of `x^2-10 a x-11 b=0a r ec ,ddot` then find the value of `a+b+c+ddotw h e na!=b!=c!=ddot`

Answer 1

Correct Answer - 1210
We have `a+b=10c,ab=-11d`
and `c+d=10a,cd=-11b`
`:.a+b+c+d=10(a+c)`
and `abcd=121bd`
`impliesb+d=9(a+c)`
and `ac=121`
Next `a^(2)-10ac=11d=0`
and `c^(2)-10ac-11b=0`
`impliesa^(2)+c^(2)-20ac-11(b+d)=0`
`implies (a+c)^(2)-22xx121-99(a+c)=0`
`impliesa+c=121` or `-22`
IF `a+c=-22impliesa=c` rejecting these values ow have
`a+c=121`
`:.a+b+c=d=10(a+c)=1210`