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3 years ago

Which expression represents the number 5i4+2i3+8i2+−4 rewritten in a+bi form?

Mathematics

2 answers:

aniked [119]3 years ago

8 0

Remember
i²=-1 so
i³=-i
i⁴=1

so
5i⁴+2i³+8i²-4
5(1)+2(-i)+8(-1)-4
5-2i-8-4
-7-2i is the form

Vinvika [58]3 years ago

6 0

Answer:

Thats not the answer. I need help with this answer too.

These are the answers we're supposed to choose from:

−3+2i

5+0i

5−2i

−3−4i

−3+0i

Which one is it?

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Answer:

A. H(x) is an inverse of F(x)

Step-by-step explanation:

The given functions are:

$F(x)=\sqrt{x-2}$

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We compose F(x) and G(x) to get:

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$(F\circ G)(x)=\sqrt{(x-2)^2-2}$

$(F\circ G)(x)=\sqrt{x^2-4x+4-2}$

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Hence G(x) is not an inverse of F(x).

We now compose H(x) and G(x).

$(F\circ H)(x)=F(H(x))$

$(F\circ H)(x)=F(x^2+2)$

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We simplify to get:

$(F\circ H)(x)=\sqrt{x^2}$

$(F\circ H)(x)=x$

Since $(F\circ H)(x)=x$ , H(x) is an inverse of F(x)

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3 years ago

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Answer:

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|z|=5 unit

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Step-by-step explanation:

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