Answer Happy

Question 3: (a) Show that ∣∣​sinαsinβsinγ​cosαcosβcosγ​sin(α+δ)sin(β+δ)sin(γ+δ)​∣∣​=0 (b) Solve by Cramer's rule, if it applies, otherwise solve any other method: x1​−3x2​+x3​2x1​−x2​4x1​−3x3​​=4=−2=0​ (c) Find the values of k for which the matrix A is invertible. A=⎣⎡​13k​213​462​⎦⎤​