Let
f(x)=x4−10x3+37x2−60x+36=0 At x=1,f(1)=1−10+37−60+36=0 At x=2,f(2)=(24−10(23+37(22...−60(2+36=0=16−80+148−120+36=200−200=0So,
x=2 is a factor of
f(x)Similarly
x=3 is a factor of
f(x)∴f(x)=(x−2)2(x−3)2∴ Original roots are
2,2,3,3The distinct roots are 2 and 3
There are three possible pairs of distinct roots
(i) Increase the two
2s by 1
(ii) Increase the two
3s by 1
(iii) Increase one 2 and one 3 by 1
Let us assume we choose one root 2 and one root 3 to increase by 1
Since, these distinct roots.
Increase one ' 2 ' by
1:2+1=3Increase one ' 3 ' by
1:3+1=4Other two roots ( 2 and 3 ) are kept fixed
∴ New sets of roots of he transformed equation is
3,4,2,3Let the transformed equation be
g(x). its roots are
2,3,3,4∴g(x)=(x−2)(x−3)(x−3)(x−4)=(x−2)(x−3)2(x−4)The common roots are value of
x for which
f(x)=0 and
g(x)=0∴ Common roots are
2,3,3∴ Number of common roots
=3