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If a is the smallest side of a triangle and a,b,c are in A.P. prove that `"cos" A=(4c-3b)/(2c)`

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CHHAYA PUBLICATION-MISCELLANEOUS EXAMPLES-TRIGONOMETRY
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  2. If the sides a,b,c of a triangle ABC are in A.P., prove that cosA "cot...

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  3. If a is the smallest side of a triangle and a,b,c are in A.P. prove th...

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  4. In a triangle ABC if b+c=3a then find the value of cot(B/2)cot(C/2)

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  5. If the medium AD is perpendicular to the side AB in the triangle ABC, ...

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  6. Show that the perimeter of any triangle is equal to 2 "cos" (A)/(2)...

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  8. If the three side of a triangle be a, b, c and tan theta=(2 sqrt(ab))...

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  11. Show that : "sin" 2(pi)/(7)+ "sin"(4pi)/(7)-"sin" (6pi)/(7) =4 "sin"...

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  13. The length of hypotenuse and one side of a right -angle triangle are ...

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  14. If "cos" A=(3)/(4), show that 32 "sin" (A)/(2) "sin" (5A)/(2)=11

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  16. If tan (pi cot theta )= cot (pi tan theta), then show that tan theta= ...

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  17. If tan (pi cos theta)= cot (pi sin theta), show that cos (theta-(pi)/(...

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  18. If u(n)=2 cos n theta, then show that u(n+1)= u(1)u(n)-u(n-1), hence, ...

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  20. If (sin theta + cos theta )=sqrt(2) cos theta , show that cot theta =...

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