What is the standard form of (2+3i)(4-7i)/(1-I)

Mathematics

2 answers:

AlladinOne [14]3 years ago

8 0

I believe in standard form this would be 31/2 + 27i/2

sergij07 [2.7K]3 years ago

8 0

Standard form is a+bi where a is the real part and bi is the imaginary part

we need to rationalize the denomenator

remember difference of 2 perfect squares
(a-b)(a+b)=a²-b²
so

in denom we got (1-i)
mulitply whole fraction by (1+i)/(1+i)
(2+3i)(4-7i)(1+i)/(1²-i²)
(2+3i)(4-7i)(1+i)/(1-(-1))
(2+3i)(4-7i)(1+i)/(1+1)
(2+3i)(4-7i)(1+i)/(2)
simplfy top part
(31+27i)/2
31/2+27i/2

the standard form is
$\frac{31}{2}+ \frac{27}{2}i$

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2^2 + (2√3)^2 = y^2 Please help!

IrinaK [193]

Answer:

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Step-by-step explanation:

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6700 dollars is placed in an account with an annual interest rate of 8%. How much will be in the account after 24 years, to the

daser333 [38]

$\bf \qquad \textit{Simple Interest Earned Amount}\\\\
A=P(1+rt)\qquad 
\begin{cases}
A=\textit{accumulated amount}\\
P=\textit{original amount deposited}\to& \$6700\\
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t=years\to &24
\end{cases}
\\\\\\
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