Answer: 1.
- A 0
- B 1
- C -1
- D 2
Correct answer: B. 1
Explanation: Direct substitution test: put x = 1 into ax²+bx+c: a(1)²+b(1)+c = a+b+c = 0 (given). So x=1 satisfies the equation identically whenever a+b+c=0. Answer: 1 is always a root
A complex number z = a+ib is plotted as a point (or vector from the origin) on the Argand plane, with the real part along the horizontal axis and the imaginary part along the vertical; its modulus |z| is the vector's length, and its argument θ is the angle from the positive real axis.
Concept context
Complex numbers in a+ib form, modulus, argument, polar form, cube roots of unity, and quadratic equations with complex roots
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