➡️ Visualizing one of the most beautiful trigonometric transformations — cos(π/2 θ) = −sinθ. A simple phase shift of π/2 rotates the cosine wave, flips its direction, and transforms it into negative sine. Instead of memorizing identities, watch how geometry, rotation, and motion reveal the truth behind the formula. When mathematics is visualized, identities stop being rules — they become experiences ➡️ Follow @equationacademy for more #maths #trigonometry #physics #science #technology | Equation