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3 years ago

Evaluate the dot product of (5,7) and (-8,2)

Mathematics

2 answers:

Viefleur [7K]3 years ago

6 0

You have to multiple and then add to get
(5)(-8)+(7)(2)=-26

seraphim [82]3 years ago

6 0

Answer:

A=Point (5,7) when represented in terms of vector = 5 i + 7 j

B=Point (-8,2) ,when represented in terms of vector = -8 i + 2 j

Dot Product of two vectors = A.B

Keep in mind

1.⇒i.i=1, j.j=1,i.j=j.i=0

2.Dot product of two vectors is Scalar Quantity.

So,→ A. B= (5 i + 7 j) . (-8 i +2 j)

= 5 × -8 +7 × 2

= -40 +14

= -26

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4 sq.units

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3 years ago

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Genrish500 [490]

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3 years ago

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Answer:

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r is the interest rate = r

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I = P*r*t

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3 years ago

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Answer:

Step-by-step explanation:

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