Q.During which part of the oscillation are the two (velocity and displacement) along the same direction?

Velocity and displacement have the same sign (same direction) when the particle is moving away from the mean position toward an extreme: on the positive side it moves in the +x direction (both positive), and on the negative side it moves in the −x direction (both negative). …

Velocity and displacement have the same sign (same direction) when the particle is moving away from the mean position toward an extreme: on the positive side it moves in the +x direction (both positive), and on the negative side it moves in the −x direction (both negative). During these quarter-cycles the speed is decreasing as t …

Answer from the section this box belongs to (§5.5 of the Balbharati Std-XII Physics textbook) — apply the …

Answering loosely — tie the reasoning to this chapter's ow …