a+b+c=180 sin2a+sin2b-sin2c=4cosacosbcosc
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Heya friends....✅
Here is ur answer...
=================
Question is wrong .. question should be,A+B+C÷180° ,sin2A+sin2B-Sin2C=4cosA*cosB*sinC
from lhs ...
=Sin2A+sin2B+sin2C
=2sin(2A+2B)/2*cos(2A-2B)/2-sin2C
=2sin(A+B)*cos(A-B)-sin2C
=2sin(π-c)*cos(A-B)-2sinC*cosC
=2sinC*[cos(A-B)+cosC]
=2sinC[cos(A-B)+cos(A+B)
=2sinC[cos(A-B)+cos(A+B) 【° • °cos(π-¢)=-cos¢】
=2sinC[cos(A-B)+cos(A+B)]>>
[• ° •cos(π-¢)=-cos¢]
cosC+CosD=2cos(C+D)*cos(C-D) here appling
then ....2sinC*2cosA*cosB
=>4cosA*cosB×sinC..Rhs ...
----------------------------------
hope it helps you..
@Rajukumar☺☺
now,,,,.....2sinC*cos
Here is ur answer...
=================
Question is wrong .. question should be,A+B+C÷180° ,sin2A+sin2B-Sin2C=4cosA*cosB*sinC
from lhs ...
=Sin2A+sin2B+sin2C
=2sin(2A+2B)/2*cos(2A-2B)/2-sin2C
=2sin(A+B)*cos(A-B)-sin2C
=2sin(π-c)*cos(A-B)-2sinC*cosC
=2sinC*[cos(A-B)+cosC]
=2sinC[cos(A-B)+cos(A+B)
=2sinC[cos(A-B)+cos(A+B) 【° • °cos(π-¢)=-cos¢】
=2sinC[cos(A-B)+cos(A+B)]>>
[• ° •cos(π-¢)=-cos¢]
cosC+CosD=2cos(C+D)*cos(C-D) here appling
then ....2sinC*2cosA*cosB
=>4cosA*cosB×sinC..Rhs ...
----------------------------------
hope it helps you..
@Rajukumar☺☺
now,,,,.....2sinC*cos
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