If sin 3A =cos (A-26°) ,where 3Ais an acute angle ,find the value of

1.	If sin 3A =cos (A-26°) ,where 3Ais an acute angle ,find the value of A
Answer» If we change the sin to cos so we do 90 -3A =cos A- 26 cos se cos cancel 90-3a= a-26 4a = 116 a= 26 Sol= Given that Sin 3A = cos (A-26°) We know that SinA= cos(90-A) SO, Cos( 90-3A)=cos(A-26°) 90+26= A+3A 116=4A A=116÷4 A=29. Ans This question is given in NCERT also. Example 10 and Pg no. 189. A=29 my answer A= Sin3A=cos(90-3A). Then putting the value. Cos and Cos get cancelled then. 90-3A=A-26. Then 90+26=A+3A. 116=4A. A=116/4. A=29. -- answer

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