If in a triangle `A B C ,` the side `c` and the angle `C` remain constant, while the remaining elements are changed slightly, show that `(d a)/(cosA)+(d b)/(cosB)=0.`

If in a triangle ABC, the side c and the angle C remain constant while the remaining elements are changed slightly, show that (da)/(cosA)+(db)/(cosB)=0

If in a triangle ABC, the side c and the angle C remain constant,while the remaining elements are changed slightly,show that (da)/(cos A)+(db)/(cos B)=0

If in a triangle A B C , the side c and the angle C remain constant, while the remaining elements are changed slightly, using differentials show that (d a)/(cosA)+(d b)/(cosB)=0

If in a triangle ABC, the side c and the angle C remain constant,while the remaining elements are changed slightly,using differentials show that (da)/(csA)+(db)/(cos B)=0

If in a triangle A B C , the side c and the angle C remain constant, while the remaining elements are changed slightly, using differentials show that (d a)/(c sA)+(d b)/(cosB)=0

If in a triangle A B C , the side c and the angle C remain constant, while the remaining elements are changed slightly, using differentials show that (d a)/(c sA)+(d b)/(cosB)=0

If in a triangle A B C , the side c and the angle C remain constant, while the remaining elements are changed slightly, using differentials show that (d a)/(c sA)+(d b)/(cosB)=0

If in the triangle ABC, the side c and the angle C remain unchnged while the other sides and angles are changed slightly, show that, (da)/(cosA) + (db)/(cosB) = 0

If in a triangle the side a and the angle A remain constant, while other elements are changed slightly then