Question

1.已知两条线断的长分别为m,n,且m/n=5/4,求m+n/m的值 2.若a/b+c=b/c+a=c/a+b=k,求k

Answer 1

1.(m+n)/m

=1+n/m

=1+1/(5/4)

=1+4/5

=9/5

2.因为a/(b+c)=b/(c+a)=c/(a+b)=k

而a/(b+c)=b/(c+a)=c/(a+b)

=(a+b+c)/[(b+c)+(c+a)+(a+b)]

=(a+b+c)/2(a+b+c)

=1/2

所以

k=1/2.