Simplify the expression: (1 − 5i)(3 + 7i). 38 + 8i −32 + 8i 38 − 8i −32 − 8i

1 answer:

3 0

Your answer is 38-8i because what you do is 1 times 3 and get 3 then 1 times 7i and get 7i then you do -5i times 3 and you get -15i then -5i times 7i and you get -35i2 and the square will cancel out the negative and make it 35 then add that to the 3 and you get 38 then take the -15i +7i and get -8 do your answer is 38-8i

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<h2>Part a) </h2><h2>Explain the error in this simplification.</h2>

Given the simplified expression

$1-\frac{2}{x-2}=\frac{x+1}{x+2}$

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$0=x^2-2x-2\:\:$

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<u><em>Identifying the Main Error</em></u>

$1-\frac{2}{x-2}=\frac{x+1}{x+2}$

$1-2\left(x+2\right)=\left(x+1\right)\left(x-2\right)$ ← ERROR Starts here

<u><em>Here is the Explanation of the Error </em></u>

<u><em /></u> $\mathrm{The\:equation\:should\:have\:been\:Multiplied\:by\:LCM=}\left(x-2\right)\left(x+2\right)$ <em>. </em>In your case you wrongly multiply the equation.