Class 10 Optional Mathematics | Conditions for Parallel and Perpendicular of Vectors

Optional Mathematics, Class 10 · Vectors

Parallel and Perpendicular Vectors

Scalar product · Projection · Triangle law

By the end of this lesson you can

📐

Test whether two vectors are parallel or perpendicular

🔢

Find a scalar product from components

🔦

Explain the scalar product as length times projection

🔺

Use the triangle law to add vectors

⇉Parallel

Angle 0° or 180°

a·b = ±|a||b|

Test: x₁y₂ = x₂y₁

⊥Perpendicular

Angle 90°

a·b = 0

Test: x₁x₂ + y₁y₂ = 0

The notes are free to read in full.

Presenter notes: Today we use the scalar product to tell how two vectors sit: side by side, facing opposite ways, or at a right angle.