If vectors i+j+2k, i+pj+5k and 5i+3j+4k are linearly dependent, the value of p is what?
Please I'm looking for the explanation. i already know the answer is 2, i just don't know how.

(D) 2

Step-by-step explanation:

If two or more vectors are linearly dependent, then one of them can be expressed as a linear combination of the rest. In other words, vectors are dependent linearly on one another if the determinant of the matrix that they form is zero.

Given vectors:

i+j+2k

i+pj+5k

5i+3j+4k

Now, since they are linearly dependent, then the determinant of their matrix should be zero. i.e

Let their matrix be A and is given by;

A =  

Where;

the first column holds the i components of the vectors

the second column holds the j components of the vectors and

the third column holds the k components of the vectors

=> |A| = det(A) = 0

Now, let's calculate the determinant.

=> 4p -15 - 4 + 25 + 6 - 10p = 0

=> 4p - 10p + 12 = 0

=> 6p = 12

=> p = 2

Therefore, the value of p for which the vectors are linearly dependent is 2

d) by the cross product property, ab^2 = bc multiplied by ad

step-by-step explanation:

we are given

in the given triangle abc

angle a is 90° and segment ad is perpendicular to segment bc

we can see that

triangle(abc) and triangle(abd) are similar because they have common side and same angle (90 degree)

so, triangles(abc) and abd are similar

since, they are similar

so, the ratio of their sides must be equal

we get

now, we can cross multiply

and we get

so, this could be step to prove it

lol.

it's ok we all do this sometimes.

-aparri