HSC Science (General) 12th Board ExamMaharashtra State Board
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# Solution - The angles of the ΔABC are in A.P. and b:c=sqrt3:sqrt2 then find ∠A, ∠B, ∠C - HSC Science (General) 12th Board Exam - Mathematics and Statistics

ConceptSolution of a Triangle

#### Question

The angles of the ΔABC are in A.P. and b:c=sqrt3:sqrt2 then findangleA,angleB,angleC

#### Solution

angleA, angleB, angleC are in A.P and b:c=sqrt3:sqrt2

therefore 2B=A+C

2B=180^@-B     ...............[because A+B+C=180^@]

3B=180^@

angleB=60^@

In ΔABC by sine rule, we have

sinB/b=sinC/c

sinB/sinC=b/c

sin60^@/sinc=sqrt3/sqrt2

sqrt3/2=sqrt3/sqrt2=sinC

sinC=1/sqrt2

angle C=45^@

angleA=180^@-60^@-45^@=75^@

Thus, the angles of ΔABC are angleA=75^@,angleB=60^@,angleC=45^@

Is there an error in this question or solution?

#### APPEARS IN

2016-2017 (July) (with solutions)
Question 2.2.3 | 4 marks
Solution for question: The angles of the ΔABC are in A.P. and b:c=sqrt3:sqrt2 then find ∠A, ∠B, ∠C concept: null - Solution of a Triangle. For the courses HSC Science (General) , HSC Science (Electronics), HSC Arts, HSC Science (Computer Science)
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