हिंदी

If α and β are the complex cube root of unity, show that α2 + β2 + αβ = 0

Advertisements
Advertisements

प्रश्न

If α and β are the complex cube root of unity, show that α2 + β2 + αβ = 0

योग
Advertisements

उत्तर

α and β are the complex cube roots of unity.

∴ α = `(-1 + "i"sqrt(3))/2` and β = `(-1 - "i"sqrt(3))/2`

∴ α + β = `(-1 + "i"sqrt(3))/2 + (-1 - "i" sqrt(3))/2`

= `(-1 + "i"sqrt(3) - 1 - "i"sqrt(3))/2`

= `(-2)/2`

= – 1

and αβ = `((-1 + "i"sqrt(3))/2)((-1 - "i"sqrt(3))/2)`

= `((-1)^2 - ("i"sqrt(3))^2)/4`

= `(1 - 3"i"^2)/4`

= `(1 + 3)/4`

= 1 ..........[∵ i2 = – 1]

α2 + β2 + aβ = (α + β)2 – αβ

= (–  1)2 –  1

= 1 – 1

= 0

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 1: Complex Numbers - Exercise 1.4 [पृष्ठ २०]

APPEARS IN

बालभारती Mathematics and Statistics (Arts and Science) Part 2 [English] Standard 11 Maharashtra State Board
अध्याय 1 Complex Numbers
Exercise 1.4 | Q 4. (i) | पृष्ठ २०

संबंधित प्रश्न

If ω is a complex cube root of unity, find the value of (1 + ω2)3


If α and β are the complex cube roots of unity, show that α2 + β2 + αβ = 0.


If x = a + b, y = αa + βb and z = aβ + bα, where α and β are the complex cube roots of unity, show that xyz = a3 + b3.


If ω is a complex cube root of unity, then prove the following:  (a + b) + (aω + bω2) + (aω2 + bω) = 0.


Find the value of ω18


Find the value of ω21


Find the value of ω–105


If ω is a complex cube root of unity, show that (2 − ω)(2 − ω2) = 7


If ω is a complex cube root of unity, show that (1 + ω − ω2)6 = 64


If ω is a complex cube root of unity, show that (1 + ω)3 − (1 + ω2)3 = 0


If ω is a complex cube root of unity, show that (2 + ω + ω2)3 − (1 − 3ω + ω2)3 = 65


If ω is a complex cube root of unity, show that (a − b) (a − bω) (a − bω2) = a3 − b3


If ω is a complex cube root of unity, find the value of (1 − ω − ω2)3 + (1 − ω + ω2)3


If ω is a complex cube root of unity, find the value of (1 + ω)(1 + ω2)(1 + ω4)(1 + ω8)


If α and β are complex cube roots of unity, prove that (1 − α)(1 − β) (1 − α2)(1 − β2) = 9.


If 1, α1, α2, ...... αn–1 are the roots of unity, then (1 + α1)(1 + α2) ...... (1 + αn–1) is equal to (when n is even) ______.


If the cube roots of the unity are 1, ω and ω2, then the roots of the equation (x – 1)3 + 8 = 0, are ______.


Simplify the following and express in the form a + ib.

`(3i^5 + 2i^7 + i^9)/(i^6 + 2i^8 + 3i^18)`


If w is a complex cube root of unity, show that `((a+bw+cw^2))/(c+aw+bw^2) = w^2`


If w is a complex cube root of unity, show that `((a + bw +cw^2))/(c +aw + bw^2) = w^2`


If ω is a complex cube root of unity, then prove the following.

(ω2 + ω −1)3 = −8


If ω is a complex cube-root of unity, then prove the following:

(ω2 + ω −1)3 = −8


If ω is a complex cube-root of unity, then prove the following :

(ω2 + ω − 1)3 = − 8


Find the value of `sqrt(-3) xx sqrt(-6)`.


If w is a complex cube-root of unity, then prove the following

(w2 + w - 1)3 = - 8


 Find the value of `sqrt(-3)xx sqrt (-6)`


If w is a complex cube root of unity, show that `((a + bw + cw^2))/(c + aw + bw^2) = w^2`


If w is a complex cube-root of unity, then prove the following. 

(w2 + w - 1)3 = - 8


If w is a complex cube root of unity, show that `((a + bomega + comega^2))/(c + aomega + bomega^2) = w^2`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×