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If the number x,y,z are in H.P. , then `sqrt(yz)/(sqrt(y)+sqrt(z)),sqrt(xz)/(sqrt(x)+sqrt(z)),sqrt(xy)/(sqrt(x)+sqrt(y))` are inA. APB. GPC. HPD. None of these |
Answer» Correct Answer - A `:.x,y,z` are in HP. `:.(1)/(x),(1)/(y),(1)/(z)` are in AP. `:.(1)/(x)-(1)/(y)=(1)/(y)-(1)/(z)" " ".......(i)"` `(sqrtyz)/(sqrt(y)+sqrt(z))=(1)/((1)/(sqrt(y))+(1)/(sqrt(z)))=a" " [" say "]` `(sqrtzx)/(sqrt(x)+sqrt(z))=(1)/((1)/(sqrt(z))+(1)/(sqrt(x)))=b" " [" say "]` and `(sqrtxy)/(sqrt(x)+sqrt(y))=(1)/((1)/(sqrt(x))+(1)/(sqrt(y)))=c" " [" say "]` `:.(a-b)/(b-c)=((1)/((1)/(sqrt(y))+(1)/(sqrt(z)))-(1)/((1)/(sqrt(z))+(1)/(sqrt(x))))/((1)/((1)/(sqrt(z))+(1)/(sqrt(x)))-(1)/((1)/(sqrt(x))+(1)/(sqrt(y))))=((1)/(x)-(1)/(y))/((1)/(y)-(1)/(z))=(a)/(a)` `" " " " [" from Eq. (i) "]` Hence, `(sqrtyz)/(sqrt(y)+sqrt(z)),(sqrt(zx))/(sqrt(z)+sqrt(x)),(sqrt(xy))/(sqrt(x)+sqrt(z))` are in AP. |
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