Math Is Fun Forum

Sammyzayn

Guest

Matrice questions. Please help.

Can anyone help, I've not a clue for these?

-For which 3 numbers c is this matrix not invertible?

      2 c c
A=  c c c
      8 7 c

               cosx  -sinx   0
- If F(x)=  sinx    cosx  0
               0        0      1

Show that F(x).F(y)= F(x+y)

and finaly

- A linear transformation T maps A(1,2) to A'(-4,6) and B'(6,3) to B'(3,0).
Find the following:
(i) The matrix T .
(ii) The image of the point K(-5,-2) under T .

If anyone can help ASAP it would be hugely appreciated. I'm really stuggling to take it in :-/

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Matrice questions. Please help.

For Q1, use the fact that a matrix is non-invertible if its determinant is 0. Do you know how to calculate the determinant of that matrix?

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