Two vectors are given by a = 8.6i + 5.1 j and b = 931 + 9.5. Find
(a). [a xb]
(b). a. b ,
(c) a + b . b , and
(d) the component of a along the direction of b.

Assuming b = 9.3i + 9.5j (b = 931 + 9.5 is wrong):

a) a×b = 34.27k

b) a·b = 128.43

c) (a + b)·b = 305.17

d) The component of a along the direction of b = 9.66

Explanation:

Assuming b = 9.3i + 9.5j (b = 931 + 9.5 is wrong) we can proceed as follows:  

a) The vectorial product, a×b  is:

b) The escalar product a·b is:

c) Asumming (a + b)·b instead a+b·b we have:

d) The component of a along the direction of b is:

I hope it helps you!                        

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what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2