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Simplify : 4-4+5-9-3-16

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Question

Simplify : `4sqrt(-4) + 5sqrt(-9) - 3sqrt(-16)`

Sum
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Solution

`4sqrt(-4) + 5sqrt(-9) - 3sqrt(-16)`

`= 4sqrt(4 xx -1) + 5sqrt(9 xx -1) - 3sqrt(16 xx - 1)`

= 4 × 2i + 5 × 3i – 3 × 4i

= 8i + 15i – 12i

= (8 + 15 – 12)i

= 11i

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Chapter 1: Complex Numbers - Exercise 1.1 [Page 5]

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