Show that (b+c) cos ((B+C)/( 2)) =a co...

Show that `(b+c) cos ((B+C)/( 2)) =a cos ((B-C)/( 2))`

Text Solution

Verified by Experts

The correct Answer is:

`a cos ((B-C)/(2))`

Promotional Banner

Promotional Banner

Topper's Solved these Questions

PROPERTIES OF TRIANGLES
VIKRAM PUBLICATION ( ANDHRA PUBLICATION)|Exercise TEXTUAL EXERCISES ( EXERCISE - 10(a) ) III.|23 Videos
PROPERTIES OF TRIANGLES
VIKRAM PUBLICATION ( ANDHRA PUBLICATION)|Exercise TEXTUAL EXERCISES ( EXERCISE - 10(b) ) I.|5 Videos
PROPERTIES OF TRIANGLES
VIKRAM PUBLICATION ( ANDHRA PUBLICATION)|Exercise TEXTUAL EXERCISES ( EXERCISE - 10(a) ) I.|12 Videos
PRODUCT OF VECTORS
VIKRAM PUBLICATION ( ANDHRA PUBLICATION)|Exercise SOLVED PROBLEMS|46 Videos
STRAIGHT LINE
VIKRAM PUBLICATION ( ANDHRA PUBLICATION)|Exercise TEXTUAL EXERCISES (EXERCISE-3(e)) |32 Videos

VIKRAM PUBLICATION ( ANDHRA PUBLICATION)-PROPERTIES OF TRIANGLES-TEXTUAL EXERCISES ( EXERCISE - 10(a) ) II.

Prove that a cos A + b cos B + c cos C = 4 R sin A sin B sin C.
Text Solution
|
In Delta , sum a^(3) sin (B-C) =
Text Solution
|
Show that (a sin (B-C))/( b^(2) - c^(2)) - ( b sin (C-A))/( c^(2...
Text Solution
|
Prove that (a)/(bc)+(cosA)/(a)=(b)/(ca)+(cosB)/(b)=(c)/(ab)+(cosC)/(c)
Text Solution
|
Prove that (1+cos(A-B)cosC)/(1+cos(A-C)cosB)=(a^(2)+b^(2))/(a^(2)+c^(2...
Text Solution
|
If C=60^(@), " then show that"(a)/(b+c)+(b)/(c+a)=1
Text Solution
|
If C = 60 ^(@) then show that (b)/( c^(2) -a^(2)) + (a)/( c^(2) ...
Text Solution
|
In Delta ABC if a: b: c = 7 : 8: 9 , then cos A : cos B : cos C =
Text Solution
|
Show that (cosA)/(a)+(cosB)/(b)+(cosC)/(c)=(a^(2)+b^(2)+c^(2))/(2abc)
Text Solution
|
Prove that ( b- a cos C) sin A = a cos A sin C
Text Solution
|
In Delta ABC , a sin ^(2) "" ( C ) /(2) + c sin ^(2) "" (A ) /(2) ...
Text Solution
|
If b +c =3a , then find the value of cot.(B)/(2)cot.(C)/(2)
Text Solution
|
Show that (b+c) cos ((B+C)/( 2)) =a cos ((B-C)/( 2))
Text Solution
|
In Delta ABC show (beta^2 - chi^2 )/( alpha^2) = sigmalnu((B-X))/((B+X...
Text Solution
|