Two projectiles are fired at different angles with the same magnitude of velocity, such that they have the same range. At what angles they might have been projected ?

We know that,  R=u2sin⁡2θgGiven that, R1=R2  and  u1=u2∴ R1=u14sin⁡2θg and  R2=u22sin⁡290∘−θg∴ sin⁡2θ=sin⁡290∘−θ=cos⁡2θSolving we get, θ=25∘. The other angle is 90∘−25∘=65∘