# How to find the 4 value unknown in a matrix?

• How to find the 4 value unknown in a matrix?

Answer #1 | 20/12 2013 00:58
|a b| |2| = |3| |c d| |1| = |4| Multiply the 2x2 matrix times the 2x1 matrix to get the two equations. (a)(2) + (b)(1) = (3) (c)(2) + (d)(1) = (4) 2a + b = 3 2c + d = 4 as you now have two equations in 4 unknowns, and the two unknowns in one equation do not appear in the other equation, all you can do is solve each equation independently for its two unknowns. 2a + b = 3 b = (-2a) + 3 a = -(1/2)*(b) + (3/2) 2c + d = 4 d = (-2c) + 4 c = -(1/2) + 2 This problem is just busy work.
Positive: 75 %

The possible values for X are 1, 2, 3, 4, 5, and 6, all equally likely ... then the expected value of the matrix is defined as the matrix of expected values:
Positive: 75 %
Matrix differential equation ... equation for an unknown function of one or several variables that relates the values of the function itself ...
Positive: 70 %
How to find the value of λ inside a 4x4 matrix that results in determinant = 0 ... picture below this a 4x4 matrix with an unknown value, ...