Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    8
    ReputationRep:
    Prove |z1z2|=(z1)(z2) if z1=1+isqrt3 and z2=-3-3i
    Offline

    9
    ReputationRep:
    I think I must be interpreting this wrong. When you say (z1)(z2), do you just mean the product of the complex numbers? If so, then that is itself a complex number. But |z1z2| is a real number, so they can't be equal.
    • Thread Starter
    Offline

    8
    ReputationRep:
    (Original post by Pangol)
    I think I must be interpreting this wrong. When you say (z1)(z2), do you just mean the product of the complex numbers? If so, then that is itself a complex number. But |z1z2| is a real number, so they can't be equal.
    That's what I was thinking I got the modulus to be 6sqrt2 and then the product to be a complex number, maybe I read the question wrong, I'm not sure, I'll ask my teacher, thanks for confirming this haha
    Offline

    6
    ReputationRep:
    I think you mean prove |Z1Z2|=(Z1)(Z2).
    • Community Assistant
    Offline

    19
    ReputationRep:
    Perhaps the question should be show |z_1 z_2| = |z_1| |z_2| as that is generally true.
    Offline

    6
    ReputationRep:
    Here's the working out.
    Name:  IMG_20170106_212413.jpg
Views: 14
Size:  443.5 KB
    • Community Assistant
    Offline

    19
    ReputationRep:
    (Original post by MiladAhmed)
    Here's the working out.
    Please could you read the Forum Rules at the top of the Maths Forum. Full solutions are not permitted here. Please just give hints and let people do the work themselves.
    Offline

    6
    ReputationRep:
    (Original post by Mr M)
    Please could you read the Forum Rules at the top of the Maths Forum. Full solutions are not permitted here. Please just give hints and let people do the work themselves.
    Whoops. I'm a newbie here, but I'll remember this in the future.
    Offline

    6
    ReputationRep:
    *|z1z2|=|z1||z2|
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    What newspaper do you read/prefer?
    Useful resources

    Make your revision easier

    Maths

    Maths Forum posting guidelines

    Not sure where to post? Read the updated guidelines here

    Equations

    How to use LaTex

    Writing equations the easy way

    Student revising

    Study habits of A* students

    Top tips from students who have already aced their exams

    Study Planner

    Create your own Study Planner

    Never miss a deadline again

    Polling station sign

    Thinking about a maths degree?

    Chat with other maths applicants

    Can you help? Study help unanswered threads

    Groups associated with this forum:

    View associated groups
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Quick reply
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.