Please help with 2 and 3

2. Given the vectors a = (d1, d2, a3) and b=(b1, b2, b3) show that a x b - -bx a. [C-5] 3. Given the vectors a, b, and c, show how to construct the following vectors using the triangle law of vector addition. Use a ruler and label your vectors [C-6]. a i) a - b in cta - b iii) - a - 20