Resistive force

The name is a category, not a mechanism. AP Physics C: Mechanics EK 2.9.A.1 defines a resistive force as a velocity dependent force in the opposite direction of an object's velocity, giving $\vec{F}_r = -k\vec{v}$ as its example. Air resistance and fluid drag are the physical cases; the definition is about how the force scales.

Velocity dependence is the whole distinction from friction. In the AP model, kinetic friction between two solid surfaces does not depend on speed: the sheet prints $\lvert \vec{F}_f \rvert \leq \lvert \mu \vec{F}_N \rvert$, with no $v$ in it. A resistive force is defined by the $v$ that friction lacks, which is why one gives a constant deceleration and the other does not.

Only one course develops it. Resistive forces get a topic of their own in C: Mechanics, 2.9. EK 2.9.A.2 says applying Newton's second law to an object under a resistive force results in a differential equation for velocity, EK 2.9.A.2.i solves it by separation of variables, and EK 2.9.A.2.iii states that position, velocity and acceleration under $\vec{F}_r = -k\vec{v}$ are exponential in time, with asymptotes set by the initial conditions and the forces on the object. The algebra-based exams assume air resistance is negligible unless a question says otherwise.

No equation sheet prints one. The C: Mechanics equations appendix carries no resistive force expression, so $\vec{F}_r = -k\vec{v}$ comes with the problem or from memory.

The asymptote is terminal velocity, which EK 2.9.A.3 defines as the maximum speed reached when a constant force and a resistive force in opposite directions leave zero net force.