1. Show that a projectile thrown with a given speed will have equal ranges for two complementary angles of projection?

As we know the formulae of range Kurma.

As the question describes that the angle are complementary which means if one of the angle is a , then another is {90-a}.

So put the values of both of them R1 and R2 ranges .

You will get to know that both of them are equal.

Thats simple.

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