stuck on questions if someone can help

Question 8 - 5 marks You should be able to answer this question after studying Unit 10. Find the coefficient of a-9 in the binomial expansion of 4a3 1 16a4 Question 9 - 5 marks You should be able to answer this question after studying Unit 12. Find, in its simplest form, the quadratic equation with the following pair solutions: 4 + 52. Question 10 - 8 marks You should be able to answer this question after studying Unit 12. (a) Given the complex numbers 147 z = 3 cos + i sin 9 9 and 10TT 10TT w = 15 COS 9 + isin 9 find zw, giving your answer in Cartesian form. (b) Use de Moivre's formula to find the Cartesian form of the complex number (1 - iv3) 5