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In a triangle A B C , if cos A=(sinB)/(2...

In a triangle `A B C` , if `cos A=(sinB)/(2sinC)` , show that the triangle is isosceles.

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To show that triangle \( ABC \) is isosceles given that \( \cos A = \frac{\sin B}{2 \sin C} \), we can follow these steps: ### Step 1: Start with the given equation We have: \[ \cos A = \frac{\sin B}{2 \sin C} \] ...
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RD SHARMA ENGLISH-SINE AND COSINE FORMULAE AND THEIR APPLICATIONS-All Questions
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  3. In a triangle A B C , if cos A=(sinB)/(2sinC) , show that the triangle...

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  4. In any Delta A B C , prove that: (cosA)/(bcosC+c cosB)+(cosB)/(c cos...

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  5. In any DeltaA B C ,suma(sinB-sin C)= (a) a^2+b^2+c^2 (b) a^2 (c) b...

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  7. In any A B C , prove that: Delta=(a^2-b^2)/2dot(sinAsinB)/(sin(A-B))

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  8. In any triangle A B C , prove that:Delta=(b^2+c^2-a^2)/(4cotA) .

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  9. In a triangle A B C ,a=4,b=3,/A=60^0 then c is root of the equation c^...

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  10. In any A B C ,2(bc cosA+ ca cosB+ab cosC) =

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  11. In any A B C , the value of 2a csin((A-B+C)/2) is (a)a^2+b^2-c^2 ...

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  14. In a right angled triangle ABC, write the value of sin^2 A + sin^2 B+ ...

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  15. Prove that, (asin(B-C))/(b^(2)-c^(2)) = (bsin(C-A))/(c^(2)-a^(2)) = ...

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  17. Problem on sine rule Type:-2 (i)The angle of elevation of the top of t...

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  18. (sqrt(sinA)-sqrt(sinB))/(sqrt(sinA)+sqrt(sinB)) = (a+b-2sqrt(ab))/(a-b...

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  19. Let O be a point inside a triangle A B C such that /O A B=/O B C=/O C ...

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