If x = logabc, y = logbca, z = logc ab, then -Maths 9th

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(a) x + y + z + 2 = xyz.x = logabc ⇒ ax = bc ⇒ ax + 1 = abc ⇒ a = (abc)1/(x +1) Similarly, b = (abc)1/(y + 1), c = (abc)1/(z + 1)∴ abc = \((abc)^{rac{1}{x+1}+rac{1}{y+1}+rac{1}{z+1}}\)⇒ \({rac{1}{x+1}+rac{1}{y+1}+rac{1}{z+1}}\) = 1⇒ (y + 1) (z + 1) + (x + 1) (z + 1) + (x + 1) (y + 1) = (x + 1) (y + 1) (z + 1)⇒ yz + y + z + 1 + xz + x + z + 1 + xy + y + x + 1 = xyz + xy + yz + zx + x + y + z + 1⇒ x + y + z + 2 = xyz.

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