# Are all projection orthogonal? ### Are all projection orthogonal?

The product of projections is not in general a projection, even if they are orthogonal. If two projections commute then their product is a projection, but the converse is false: the product of two non-commuting projections may be a projection .

### Is projection the same as orthogonal projection?

If you were to take an orthogonal basis containing u, then the definition of orthogonal projection would coincide with the above, more general, definition of projection. I took linear algebra with this same textbook and went through the same dilemma. ... The projection is not orthogonal in this case.

### Are orthogonal projections unique?

Orthogonal Projection: The unique vector w in subspace W that is “closest” to vector u.

### Why is orthogonal projection used?

A projection P on X is called orthogonal if its range and null space are orthogonal sets. Orthogonal projections have many interesting properties. If. Its range M and null space N are closed linear subspaces of X, which are also orthogonal and algebraic complements of each other.

### How do you draw orthogonal projections?

Steps used to create an orthographic projection

1. Choose a front view. ...
2. Decide how many views are needed to completely describe the object. ...
3. Draw the visible features of the front view.
4. Draw projectors off of the front view horizontally and vertically in order to create the boundaries for the top and right side views.

Prove projection is self adjoint if and only if kernel and image are orthogonal complements. Let V be an IPS and suppose π:V→V is a projection so that V=U⊕W (ie V=U+W and U∩W={0}) where U=ker(π) and W=im(π), and if v=u+w (with u∈U, w∈W) then π(v)=w.

### Does orthogonal mean parallel?

If we know that they're orthogonal, then by definition they can't be parallel, so we're done with our testing. First we'll put the vectors in standard form. Now we'll take the dot product of our vectors to see whether they're orthogonal to one another.

### Which projection has only one view?

Explanation: Orthographic projection is the representation of two or more views on the mutual perpendicular projection planes. But for oblique projection, the object is viewed in only one view.

### What are the two main types of projection?

There are two type of projection parallel and perspective.

• Parallel Projection : Parallel projections are used by architects and engineers for creating working drawing of the object, for complete representations require two or more views of an object using different planes. ...
• Perspective Projection :

### What are the 3 views?

Although six different sides can be drawn, usually three views of a drawing give enough information to make a three-dimensional object. These views are known as front view, top view and end view. Other names for these views include plan, elevation and section.

### How does the projection of a vector be orthogonal?

For the projection to be orthogonal, the vector and its projection onto the base must lie in a plane perpendicular to the base i.e if you imagine the vector to be a series of points, each of these should fall perpendicularly onto the base as shown in the pic below (sorry for the bad drawing).

### Why is synonim for orthogonal used in projective plane?

Because line along which your orginal point travel to projective plane is orthogonal to projective plane. In this context synonim for orthogonal is perpendicular which I think is more common and well undertstood word. Consider the example of a vector in 3-D projected onto a 2-D plane (let's call it base).

### What kind of projection is an orthographic projection?

Like the stereographic projection and gnomonic projection, orthographic projection is a perspective (or azimuthal) projection, in which the sphere is projected onto a tangent plane or secant plane. The point of perspective for the orthographic projection is at infinite distance.

### When was the first use of orthogonal projection?

Symbols used to define whether a projection is either Third Angle (right) or First Angle (left). The orthographic projection has been known since antiquity, with its cartographic uses being well documented. Hipparchus used the projection in the 2nd century BC. to determine the places of star-rise and star-set.