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If (2 + 3i)2 + (2 − 3i)2 = a + bi, a = and b = .

User Bvaughn
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2 Answers

3 votes

(2+3i)^2+(2-3i)^2=(4+12i+9i^2)+(4-12i+9i^2)=8+18i^2=8-18=-10

so
a=-10 and
b=0.
User Joseph Gordon
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4 votes

Answer : The value of a = -10 and b = 0

Step-by-step explanation :

As we are given the expression:


(2+3i)^2+(2-3i)^2=a+bi

Now we have to calculate the value of a and b.


(2+3i)^2+(2-3i)^2=a+bi

Using identity :


(a+b)^2=a^2+b^2+2ab


(a-b)^2=a^2+b^2-2ab


[2^2+(3i)^2+2* 2* i]+[2^2+(3i)^2-2* 2* i]=a+bi


[4+9i^2+4i]+[4+9i^2-4i]=a+bi


4+9i^2+4i+4+9i^2-4i=a+bi


4+9i^2+4+9i^2=a+bi


8+18i^2=a+bi

As we know that,
i^2=(-1)

So,


8+18(-1)=a+bi


8-18=a+bi


-10=a+bi

Thus, the value of a = -10 and b = 0

User USB
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