Definition

1. Adjective:
   • Oblique: Describing a line, plane, or direction that is slanted or at an angle that is not a right angle (90 degrees) to a given reference line or surface. It is the primary mathematical and geometric term for "xiên góc".

Usage Examples

• Adjective:
  • Đường thẳng này cắt nhau tạo thành một góc xiên. (This straight line intersects to form an oblique angle.)
  • Trong hình học, một đường xiên góc không vuông góc với mặt phẳng. (In geometry, an oblique line is not perpendicular to the plane.)

Advanced Usage

• "góc xiên": This is a common variant phrase meaning "oblique angle".
  • Tam giác này có một góc xiên. (This triangle has an oblique angle.)

Variants and Related Words

• Xiên (adj): slanting, skew. This is the root word implying a slanted direction.

  • Cây cọc được đóng xiên xuống đất. (The stake was driven slantingly into the ground.)

• Góc nhọn (n): acute angle.

• Góc tù (n): obtuse angle.
• Góc vuông (n): right angle.

Synonyms

• Slanted: positioned at an angle.
• Skew: neither parallel nor intersecting at a right angle (often used for lines in three dimensions).
• Diagonal: extending from one corner to another, often implying an oblique line within a shape.

Related Terms and Concepts

• Đường xiên: oblique line. A line that intersects another line or plane at an angle that is not 90 degrees.

  • Từ điểm A, kẻ một đường xiên đến đường thẳng BC. (From point A, draw an oblique line to line BC.)

• Hình chiếu xiên: oblique projection. A type of technical drawing projection where the projectors are parallel but strike the plane at an oblique angle.