Please solve q 33?

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1 Answer
Apr 11, 2018

The answer is "option (b)"

Explanation:

Let

x/(b+c-a)=k

y/(c+a-b)=k

z/(a+b-c)=k

Therefore,

x=(b+c-a)k

y=(c+a-b)k

z=(a+b-c)k

So,

x(b-c)+y(c-a)+z(a-b)

=k(b+c-a)(b-c)+k(c+a-b)(c-a)+k(a+b-c)(a-b)

=k(b^2-c^2-a(b-c)+c^2-a^2-b(c-a)+a^2-b^2-c(a-b))

=0

The answer is "option (b)"

"Question (31)"

Let

a/(b+c)=k, =>, a=(b+c)k

b/(c+a)=k, =>, b=(a+c)k

c/(a+b)=k, =>, c=(a+b)k

Therefore,

(a+b+c)=(b+c)k+(a+c)k+(a+b)k

(a+b+c)=(bk+ck)+(ak+ck)+(ak+bk)

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

k=1/2

Similarly if k'=1/k

k'=2

The answer is "option (d)"