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If in a !ABC , sin A, sin B and sin C ar...

If in a `!ABC` , sin A, sin B and sin C are in A.P, then

A

the altitudes are in A.P.

B

the altitudes are in H.P.

C

the medians are in G.P.

D

the medians are in A.P.

Text Solution

Verified by Experts

Let `p_(1), p_(2), p_(3)` be the altitudes of `Delta` ABC. Then,
`Delta=1/2ap_(1)=1/2bp_(2)=1/2cp_(3)`
`rArra=(2Delta)/(p_(1)).b=(2Delta)/(p_(2)),c=(2Delta)/(p_(3))`

Now,
sin A, sin B, sin C are in AP.
`rArra,b,c` are in A.P.
`rArr(2Delta)/(p_(1)),(2Delta)/(p_(2)),(2Delta)/(p_(3))` are in A.P.
`rArr1/(p_(1)),1/(p_(2)),1/(p_(3))` are in A.P. `rArrp_(1),p_(2),p_(3)` are in H.P.
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