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5. Complex Numbers and Quadratic Equations
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Q15 of 202 Page 171

If , where c is real, prove that a2 + b2 = 1 and .

Consider the given equation,


Now, rationalizing





[(a – b)(a + b) = a2 – b2]



[i2 = -1]




On comparing both the sides, we get



Now, we have to prove that a2 + b2 = 1


Taking LHS,


a2 + b2


Putting the value of a and b, we get







= 1


= RHS


Now, we have to prove


Taking LHS,


Putting the value of a and b, we get



Hence Proved


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Questions · 202
5. Complex Numbers and Quadratic Equations
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