trigonometry

Related Questions

• In triangle $ABC$ , $(b+c)\cos A+(c+a)\cos B$ $+(a+b)\cos C=$

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• If in any $\Delta ABC$ , $\cot \frac{A}{2},\cot \frac{B}{2},\cos \frac{C}{2}$ are in A. P. then

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• If the line segment joining the points $A(a,\,b)$ and $B(c,\,d)$ subtends an angle $\theta $ at the origin, then $\cos \theta $ is equal to

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• If $\tan \alpha $ equals the integral solution of the inequality $4{{x}^{2}}-16x+15<0$ and $\cos \beta $ equals to the slope of the bisector of first quadrant, then $\sin (\alpha +\beta )\sin (\alpha -\beta )$is equal to

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• If $x=a{{\cos }^{3}}\theta ,y=b{{\sin }^{3}}\theta ,$then

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