Volume of a Parallelepiped Calculator

Calculate volume and surface area using vectors, vertices, or edge lengths

Calculate Parallelepiped Volume

Vector a = a₁i + a₂j + a₃k

Vector b = b₁i + b₂j + b₃k

Vector c = c₁i + c₂j + c₃k

Calculation Results

Volume

290.000000
cubic units

Surface Area

354.634409
square units

Vector Calculations

Cross Product (a × b): (26.000, 8.000, -14.000)
Scalar Triple Product (a × b) · c: -290.000000
Volume = |Scalar Triple Product|: 290.000000

Example Calculations

Example 1: Three Vectors

Given: a = i + 2j + 3k, b = 5i - 4j + 7k, c = -5i + j + 12k

Cross Product: a × b = (26i + 8j - 14k)

Scalar Triple Product: (a × b) · c = 26(-5) + 8(1) + (-14)(12) = -290

Volume: |-290| = 290 cubic units

Example 2: Edge Lengths Method

Given: a = 5, b = 4, c = 7, α = 45°, β = 50°, γ = 63°

Formula: V = abc√(1 + 2cos(α)cos(β)cos(γ) - cos²(α) - cos²(β) - cos²(γ))

Calculation: V = 5 × 4 × 7 × √(1 + 2×0.707×0.643×0.454 - 0.5 - 0.413 - 0.206)

Volume: ≈ 75.83 cubic units

Example 3: Using Vertices

Given: P(0,0,0), Q(1,2,3), R(5,-4,7), S(-5,1,12)

Vectors: a = Q - P = (1,2,3), b = R - P = (5,-4,7), c = S - P = (-5,1,12)

Result: Same as Example 1, Volume = 290 cubic units

Volume Formulas

Scalar Triple Product

V = |(a × b) · c|

Determinant Method

|c₁ c₂ c₃|
|a₁ a₂ a₃|
|b₁ b₂ b₃|

Edge Lengths

V = abc√(1 + 2cos(α)cos(β)cos(γ) - cos²(α) - cos²(β) - cos²(γ))

Surface Area

A = 2(|a×b| + |b×c| + |a×c|)

Parallelepiped Properties

📦

Shape: 6 parallelogram faces

3 pairs of parallel faces

Vectors: Three adjacent edges

Define entire solid

Volume = 0: Vectors coplanar

All vectors in same plane

Area = 0: Vectors collinear

All vectors on same line

Real-World Applications

🏗️

Engineering

Structural analysis, material volumes

💎

Crystallography

Unit cell volumes, crystal structures

📐

Linear Algebra

Determinants, transformations

🎮

Computer Graphics

3D modeling, collision detection

Understanding Parallelepiped Volume

What is a Parallelepiped?

A parallelepiped is a three-dimensional figure formed by six parallelograms. It can be described by three vectors representing its adjacent edges. The volume represents the amount of space enclosed by this solid.

Scalar Triple Product

The volume is calculated using the scalar triple product: (a × b) · c. This combines the cross product (which gives the area of the parallelogram base) with the dot product (which projects the third vector onto the perpendicular direction).

V = |(a × b) · c|

Absolute value ensures positive volume

Calculation Methods

Vector Method: Uses three vectors directly

Most common for mathematical problems

Vertex Method: Calculates vectors from coordinates

Useful when given corner points

Edge Method: Uses lengths and angles

Practical for physical measurements

Special Cases

  • Volume = 0: Vectors are coplanar (flat shape)
  • Surface Area = 0: Vectors are collinear (line)
  • Negative scalar product: Vectors form left-handed system