Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Most Important Selected Qs for JEE AdvancedMathematicsComplex Number

Paragraph: For non-zero complex numbers z₁ and z₂ define the dot product and the cross product of z ₁ and z ₂ as follows Dot product z₁ z₂= |z₁ | |z₂ | =x₁ x₂+y₁ y₂= Re ( z ₁ z₂ ) Cross product z₁ z₂= |z₁ | |z₂ | =x₁ y₂-x₂ y₁=i m ( z ₁ z₂ ) Question: z₁ z₂+i (z₁ z₂ ) equals

Options

  1. AZ ₁ Z ₂
  2. BZ ₁ ~L ₂
  3. Cz ₁ z ₂
  4. Dz ₁ z ₂

Correct answer

C. z ₁ z ₂

Step-by-step solution

aligned & z₁ z₂+i (z₁ z₂ )= |z₁ | |z₂ | +i |z₁ | |z₂ | & = |z₁ | |z₂ | e^ where = - & = ( |z₁ | e^ -i ) ( |z₂ | e^ )=z₂ z₁ aligned

Practice Complex Number on Quantrex Academy →

More from Complex Number

The number of values of z C , satisfying the equations |z-(4+8i)|= 10 and |z-(3+5i)|+|z-(5+11i)|=4 5 , is: 2026Let S = z C : z^2 + 6 ,iz - 3 = 0 . Then _ z S z^8 is equal to : 2026Let the set of all values of k R such that the equation z( z + 2 + i) + k(2 + 3i) = 0 , z C , has at least one solution, be the interval [ , ] . Then 9( + ) is equal to: 2026Let z₁, z₂ C be the distinct solutions of the equation z^2 + 4z - (1 + 12i) = 0 . Then |z₁|^2 + |z₂|^2 is equal to : 2026Let S= z C : z^2+4z+16=0 . Then _ z S |z+ 3 i|^2 is equal to: 2026Let z be a complex number such that |z+2| = |z-2| and ( z+3 z-i ) = 4 . Then |z|^2 is equal to: 2026Let the circles C₁ : |z| = r and C₂ : |z - 3 - 4i| = 5 , z C , be such that C₂ lies within C₁ . If z₁ moves on C₁ , z₂ moves on C₂ and |z₁ - z₂| = 2 , then |z₁ - z₂| is equal to: 2026Let x and y be real numbers such that 50 ( 2x 1+3i - y 1-2i ) = 31 + 17i , i = -1 . Then the value of 10(x - 3y) is : 2026 Full Complex Number list All Most Important Selected Qs for JEE Advanced PYQs