3 years ago

What is the magnitude of -2a - 3b when a=3i+9j and b=4i-6j?

Mathematics

1 answer:

Alex787 [66]3 years ago

3 0

Answer:

Dear mcdeagon,

Answer to your query is provided below:

Magnitude of -2a-3b = -18i-6j

Step-by-step explanation:

When a = 3i+9j and b = 4i-6j

Magnitude of -2a-3b will be calculated by putting value of a and b

So, -2a-3b = -2(3i+9j)-3(4i-6j)

= -6i-18j-12i+12j = -18i-6j

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