show that a(b^2+c^2).cos A+b(c^2+a^2).cos B+c(a^2+b^2).cos C=3 abc
Answers
Answer:
Solution :
From sine law, we have,<br>
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<br> Now,<br>
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FAQs on Sine And Cosine Formulae And Their Applications
Sine formu
Problem on sine rule Type:-1(i) In a
; If
;find
(ii) In a
; the angle of a triangle are in AP ; It is being given that
An object is observed from three points
in the same horizontal line passing through the base of the object. The angle of elevation at
is twice and at
is thrice than that at
. If
prove that the height of the object is
The law of cosines proof :
In
prove that