Modulus, Square Root and Argument of Complex Number
Complex Numbers and Quadratic Equation

117831 If \(f(z)=\frac{7-z}{1-z^2}\), where \(z=1+2 i\), then \(|f(z)|\) is equal to :

1 \(\frac{|z|}{2}\)
2 \(|z|\)
3 \(2|z|\)
4 None of these
Complex Numbers and Quadratic Equation

117832 If \(\left|\mathbf{z}_1\right|=2,\left|\mathbf{z}_2\right|=3,\left|\mathbf{z}_3\right|=4\) and \(\left|2 z_1+3 z_2+4 z_3\right|=4\), then
\(\left|8 z_2 z_3+27 z_3 z_1+64 z_1 z_2\right|\) is equal to

1 24
2 48
3 72
4 96
Complex Numbers and Quadratic Equation

117833 The root of the equation \(2(1+i) x^2-4(2-i) x-5-3 i=0\) which has greater modulus is

1 \(\frac{3-5 i}{2}\)
2 \(\frac{5-3 i}{2}\)
3 \(\frac{3-\mathrm{i}}{2}\)
4 None
Complex Numbers and Quadratic Equation

117834 The equation \(z \bar{z}+(2-3 i) z+(2+3 i) \bar{z}+4=0\) represents a circle of radius

1 2
2 3
3 4
4 6
Complex Numbers and Quadratic Equation

117831 If \(f(z)=\frac{7-z}{1-z^2}\), where \(z=1+2 i\), then \(|f(z)|\) is equal to :

1 \(\frac{|z|}{2}\)
2 \(|z|\)
3 \(2|z|\)
4 None of these
Complex Numbers and Quadratic Equation

117832 If \(\left|\mathbf{z}_1\right|=2,\left|\mathbf{z}_2\right|=3,\left|\mathbf{z}_3\right|=4\) and \(\left|2 z_1+3 z_2+4 z_3\right|=4\), then
\(\left|8 z_2 z_3+27 z_3 z_1+64 z_1 z_2\right|\) is equal to

1 24
2 48
3 72
4 96
Complex Numbers and Quadratic Equation

117833 The root of the equation \(2(1+i) x^2-4(2-i) x-5-3 i=0\) which has greater modulus is

1 \(\frac{3-5 i}{2}\)
2 \(\frac{5-3 i}{2}\)
3 \(\frac{3-\mathrm{i}}{2}\)
4 None
Complex Numbers and Quadratic Equation

117834 The equation \(z \bar{z}+(2-3 i) z+(2+3 i) \bar{z}+4=0\) represents a circle of radius

1 2
2 3
3 4
4 6
Complex Numbers and Quadratic Equation

117831 If \(f(z)=\frac{7-z}{1-z^2}\), where \(z=1+2 i\), then \(|f(z)|\) is equal to :

1 \(\frac{|z|}{2}\)
2 \(|z|\)
3 \(2|z|\)
4 None of these
Complex Numbers and Quadratic Equation

117832 If \(\left|\mathbf{z}_1\right|=2,\left|\mathbf{z}_2\right|=3,\left|\mathbf{z}_3\right|=4\) and \(\left|2 z_1+3 z_2+4 z_3\right|=4\), then
\(\left|8 z_2 z_3+27 z_3 z_1+64 z_1 z_2\right|\) is equal to

1 24
2 48
3 72
4 96
Complex Numbers and Quadratic Equation

117833 The root of the equation \(2(1+i) x^2-4(2-i) x-5-3 i=0\) which has greater modulus is

1 \(\frac{3-5 i}{2}\)
2 \(\frac{5-3 i}{2}\)
3 \(\frac{3-\mathrm{i}}{2}\)
4 None
Complex Numbers and Quadratic Equation

117834 The equation \(z \bar{z}+(2-3 i) z+(2+3 i) \bar{z}+4=0\) represents a circle of radius

1 2
2 3
3 4
4 6
Complex Numbers and Quadratic Equation

117831 If \(f(z)=\frac{7-z}{1-z^2}\), where \(z=1+2 i\), then \(|f(z)|\) is equal to :

1 \(\frac{|z|}{2}\)
2 \(|z|\)
3 \(2|z|\)
4 None of these
Complex Numbers and Quadratic Equation

117832 If \(\left|\mathbf{z}_1\right|=2,\left|\mathbf{z}_2\right|=3,\left|\mathbf{z}_3\right|=4\) and \(\left|2 z_1+3 z_2+4 z_3\right|=4\), then
\(\left|8 z_2 z_3+27 z_3 z_1+64 z_1 z_2\right|\) is equal to

1 24
2 48
3 72
4 96
Complex Numbers and Quadratic Equation

117833 The root of the equation \(2(1+i) x^2-4(2-i) x-5-3 i=0\) which has greater modulus is

1 \(\frac{3-5 i}{2}\)
2 \(\frac{5-3 i}{2}\)
3 \(\frac{3-\mathrm{i}}{2}\)
4 None
Complex Numbers and Quadratic Equation

117834 The equation \(z \bar{z}+(2-3 i) z+(2+3 i) \bar{z}+4=0\) represents a circle of radius

1 2
2 3
3 4
4 6