Projectile Motion Analysis: Time in Air Calculation

[Blox_Nitrates]

The horizontal component of the velocity does not change, but the projectile's speed (which combines horizontal and vertical components) does.
Suppose the launch speed is u and launch angle is θ above horizontal. What is the horizontal component at launch?

Voy = usinθ?

 

[haruspex]

Voy = usinθ?

That is correct for the vertical velocity at launch, but I asked for the horizontal.

 

[Blox_Nitrates]

That is correct for the vertical velocity at launch, but I asked for the horizontal.

Sorry,
Vox = ucosθ

 

[haruspex]

Right, so let's recap. The question was:
A projectile's launch speed is five times its speed at maximum height. Find launch angle θo
We have the variable v for speed at max height, we have established that this is equal to Vox = ucosθo. What does the question say about the relationship between u and v?