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In a DeltaABC, a ^(2) cos 2B+b^(2) cos 2...

In a `DeltaABC, a ^(2) cos 2B+b^(2) cos 2A+2ab cos (A-B)=`

A

(a)`a^(2)`

B

(b)`c ^(2)`

C

(c)`b ^(2)`

D

(d)`a ^(2)+ b ^(2)`

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ARIHANT MATHS ENGLISH-PROPERTIES AND SOLUTION OF TRIANGLES -Exercise For Sesssion 1
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  3. Let ABC be a triangle such that angle A =45^(@) , angle B =75^(@), the...

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  4. If the angles A, B, C of DeltaABC are in A.P. and b:c=sqrt(3):sqrt(2),...

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  7. In any triangle A B C , prove that: (a^2sin(B-C))/(sinB+s in C)+(b^2si...

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  15. In any triangle A B C , prove that: (1+cos(A-B)cos C)/(1+cos(A-C)cos B...

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  16. If the sides of a triangle ABC are in AP and 'a' is the smallest side,...

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  17. In a DeltaABC, a ^(2) cos 2B+b^(2) cos 2A+2ab cos (A-B)=

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