MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
Grade: 12
        If |z-2-i|=4 then find the minimum value of |3z-6+15i| plz reply fast as possible
one year ago

Answers : (2)

kashish bhatia
25 Points
							|z-2-i|=4z-2-i=+4,-4z=6+i,(-2+i)1.z=6+i|3(6+i)-6+15i|=|12+18i|2.z= -2+I|3(-2+i)-6+15i|=|12-18i|=MINIMUM
						
one year ago
Samyak Jain
333 Points
							
|z – 2 – i| = 4  or  |z – (2 + i)| = 4  
Above equation represents a circle centred at (2,1) with radius 4 units.
\therefore Eqof circle is (x – 2)+ (y – 2)2 = 16            ................(1)
Minimum value of  |3z-6+15i| means minimum value of
3|z – (2 – 5i)|. 
First we’ll find the minimum value of |z – (2 – 5i)| & multiply it by 3.
It denotes least distance from a point on the circle & point (2, – 5).
(2, – 5) lies below the circle in coordinate axes system.
Line through center (2,1) & (2, – 5) is parallel to y-axis &
its eqis x = 2          …................(2)
points of intersection of (1) & (2) are (2,5) & (2, – 3).
By geometry, (2, –3) is nearest to (2, –5) of all points on the circle. 
\therefore Distance between (2, –3) & (2, –5) is 2 units, i.e., 
minimum value of |z – (2 – 5i)| is 2 and hence 
the minimum value of |3z-6+15i| = 3|z – (2 – 5i)| = 3*2
                                                      = 6
one year ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution


Course Features

  • 101 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions


Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details