Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 1 - No. 9)

In a three-dimensional problem involving finding lengths or angles, which of the following is/are useful tools?

Identifying right-angled triangles within the object.

Applying Pythagoras' theorem.

Using the sine rule to find angles.

Using the Cosine rule.

Right-angled triangles, Pythagoras, and Cosine Rule help in solving 3D problems.