110k views
4 votes
Help please

Find the dot product, a * b.

A=6i+5j, b= -5i +4i

A.50 B. <1,9> C. -10 D. <-30,20>

I think D is right but I have doubts

2 Answers

3 votes
I hope this helps you


❗i^2= -1


A=11i


B= -i


A×B= 11i×(-i)


A×B= -11.i^2


A×B=11
User Jonathan Roth
by
8.9k points
1 vote
C is the answer ( i got 100%)
User Ivan Neeson
by
7.0k points

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