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MATH1015 Linear Algebra 1 - Workshop 7 Cramer's Rule 4. Use Cramer's rule to solve the following systems of linear equations. (i) 3.x1 - 2x2 = 6 -5.21 + 4x2 = 8 (ii) x1 + 2x2 = 3 321 + 12 = -1 5. Use Cramer's rule to solve the following system for 23 without solving for the re- maining variables. 1 + 2 + 3 = 0 2x1 - 5x2 - 3x3 = 10 4.x1 + 8x2 + 203 = 4 Cross and scalar triple products using determinants 6. For the following pairs of vectors, determine a x b by taking the determinant of an appropriate matrix. (i) a = [3, 2, 1], b = [-1, 1,4] (ii) a = 2i + k, b= i+ j - k 7. By using an appropriate determinant, calculate the volume of the parallelepiped formed by the vectors a = [2, 6, -2], b = [-3, 2, 0] and c = [0, 1, 5]