Is it possible to contruct a 4x3 matrix b and a 3x4 matrix c such that bc is invertible?

1 answer:

3 0

Matrix B has dimensions 4x3
Matrix C has dimensions 3x4

Write out those dimensions like so: 4x3 3x4
The inner '3's match up so B*C is possible. The dimensions of B*C is 4x4 as these are the outer dimensions when lining up 4x3 3x4

Since B*C is a square matrix, it is possible that an inverse could exist. Keep in mind that this isn't a guarantee as the determinant of B*C could be zero (which would lead to BC being non-invertible). Though of course we'd need more info.

You might be interested in

in 1975 there were 130,000 tennis courts in the united states this number increased by 69% from 1975 to 1985 find the number of

strojnjashka [21]

130,000 x 1.69 = <span>219,700 tennis courts in 1985</span>

5 0

3 years ago

Which expression is prime? A) x2 - 9 B) 1 - 9x2 C) 2a2 - 25 D) 4x2 - 9

mel-nik [20]

I think the right anser would be (a)

4 0

3 years ago

Read 2 more answers

Explain how to decompose a triangle into congruent triangles. How do those decomposed pieces relate to the area of the rectangle

andre [41]

Answer: You would divide the rectangle into half, to form two congruent triangles. When you multiply the area of 1 of the triangles, it gives you the area of both triangles, and so the area of the triangle as a whole.

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

Suppose GRE Verbal scores are normally distributed with a mean of 461 and a standard deviation of 118. A university plans to rec

nirvana33 [79]

Answer:

The minimum score required for recruitment is 668.

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 461 \sigma = 118$