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If A nad B are the H.C.F and L.C.M. respectively of two algebraic expressions x and y, and A + B = x + y, then the value of $A^{3}+B^{3}$ is

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If A nad B are the H.C.F and L.C.M. respectively of two algebraic expressions x and y, and A + B = x + y, then the value of $A^{3}+B^{3}$ is
  • A$X^{3}-Y^{3}$
  • B$X^{3}$
  • C$Y^{3}$
  • D$X^{3}+Y^{3}$
Answer not set
0
CCommunity
option 4 is the right answer
0
CCommunity
Let no. are x and y and HCF = A, LCM = B

Using Rule, we have

xy = AB

x + y = A + B (given) ...(i)

(x–y)2 = (x + y)2 – 4xy

or,

(x–y)2 = (A + B)2 – 4 AB

or,

(x–y)2 = (A – B)2

or,

(x–y) = A – B ...(ii)

Using (i) and (ii),

we get x = A and y = B

$A^{3}+B^{3}=X^{3}+Y^{3}$