Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

JEE Class main Answered

Sir pls solve the following.
question image
Asked by rsudipto | 29 Dec, 2018, 11:47: AM
answered-by-expert Expert Answer
Given expression :  (1+i)n1 + (1+i3)n1 + (1+i5)n2 + (1+i7)n2 .......................(1)
 
since i = √-1  , i3 = - i  , i5 = i  and i7 = - i
 
Hence eqn.(1) becomes,  (1+i)n1 + (1-i)n1 + (1+i)n2 + (1-i)n2
 
begin mathsize 12px style f o r space a n y space p o s i t i v e space i n t e g e r space n comma space u sin g space b i n o m i a l space e x p a n s i o n w e space h a v e space left parenthesis 1 plus i right parenthesis to the power of n space equals space 1 space plus space C presuperscript n subscript 1 space i space minus space C presuperscript n subscript 2 space minus C presuperscript n subscript 3 space i space plus space C presuperscript n subscript 4 space plus space C presuperscript n subscript 5 space i space minus C presuperscript n subscript 6 space........ w e space h a v e space left parenthesis 1 minus i right parenthesis to the power of n space equals space 1 space minus space C presuperscript n subscript 1 space i space minus space C presuperscript n subscript 2 space plus C presuperscript n subscript 3 space i space plus space C presuperscript n subscript 4 space minus space C presuperscript n subscript 5 space i space minus C presuperscript n subscript 6 space........ H e n c e space left parenthesis 1 plus i right parenthesis to the power of n space plus space left parenthesis 1 minus i right parenthesis to the power of n space i s space r e a l space f o r space a n y space n end style
hence in the option list, (D) is correct answer,   i.e., n1>0 , n2 >0
Answered by Thiyagarajan K | 30 Dec, 2018, 16:12: PM

Application Videos

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
JEE main - Maths
in how many ways a team of 2 boys and 4 girls selected from 5 boys and 6 girls
Asked by pallavibirangal87 | 08 Dec, 2024, 10:18: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
if a chord of length 18 cm is 12 cm away from the centre then find the distance of 24 cm long chord from the centre
Asked by pritisindra6 | 06 Dec, 2024, 21:04: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
The number of ways in which at least one coin can be selected from 3 coins of one rupee, 4 coins of fifty paise, 5 coins of twenty paise and 6 coins of ten paise is-
Asked by kanishthkumawat | 29 Nov, 2024, 00:23: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
what is range of tan^-1 x
Asked by pawandhayal125 | 06 Oct, 2024, 10:03: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
what is 2+2
Asked by srishtipra2008 | 28 Sep, 2024, 10:33: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
n arithmetic means are inserted between the numbers 7 and 49. if the sum of these means is 364 then the sum of their squares is
Asked by yogeshsoni575 | 23 Sep, 2024, 23:01: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
consider a dodecagon then number of ways of selecting two triangles which can be made using the vertices of dodecagon so that they do not have a common side.
Asked by sumit.parsudih | 17 Sep, 2024, 22:22: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
the sum of infinite series 1/2(1/3+1/4)-1/4(1/3^2+1/4^2)+1/6(1/3^3+1/4^3)+
Asked by pritamlovevanshi5 | 15 Sep, 2024, 08:24: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
solve the equation 6x-y+3z=10 , 3x+6y=18 , x+y+5z=-10 by jacobis method with (3,0,-2) as the initial approcimate to the solution
Asked by ganeshbabugottapu7 | 12 Sep, 2024, 18:19: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
JEE main - Maths
find the inverse of a Matrix by using gauss Jordan method -2. 1. 3 A = 0. -1. 1 1. 2. 0
Asked by ganeshbabugottapu7 | 10 Sep, 2024, 07:32: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt