मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Answer the following: If x + iy = a+iba-ib, prove that x2 + y2 = 1 - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

Answer the following:

If x + iy = `("a" + "ib")/("a" - "ib")`, prove that x2 + y2 = 1

बेरीज

उत्तर

x + iy = `("a" + "ib")/("a" - "ib") = (("a" + "ib")("a" + "ib"))/(("a" - "ib")("a" + "ib"))`

= `("a"^2 + "i"^2"b"^2 + 2"abi")/("a"^2 - "i"^2"b"^2)`

= `(("a"^2 - "b"^2) + 2"abi")/("a"^2 + "b"^2)`   ...[∵ i2 = – 1]

∴ x + iy = `("a"^2 - "b"^2)/("a"^2 + "b"^2) + (2"ab")/("a"^2 + "b"^2)"i"`

Equating real and imaginary parts, we get

x = `("a"^2 - "b"^2)/("a"^2 + "b"^2)` and y = `(2"ab")/("a"^2 + "b"^2)`

∴ x2 + y2 = `(("a"^2 - "b"^2)^2)/("a"^2 + "b"^2)^2 + (4"a"^2"b"^2)/("a"^2 + "b"^2)^2`

= `("a"^4 + "b"^4 - 2"a"^2 "b"^2 + 4"a"^2"b"^2)/("a"^2 + "b"^2)^2`

= `(("a"^2 + "b"^2)^2)/("a"^2 + "b"^2)^2`

∴ x2 + y2 = 1

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 1: Complex Numbers - Miscellaneous Exercise 1.2 [पृष्ठ २२]

APPEARS IN

बालभारती Mathematics and Statistics 2 (Arts and Science) [English] 11 Standard Maharashtra State Board
पाठ 1 Complex Numbers
Miscellaneous Exercise 1.2 | Q II.13 | पृष्ठ २२

संबंधित प्रश्‍न

Express the following expression in the form of a + ib.

`((3 + sqrt5)(3 - isqrt5))/((sqrt3 + sqrt2i)-(sqrt3 - isqrt2))`


If `x – iy = sqrt((a-ib)/(c - id))` prove that `(x^2 + y^2) = (a^2 + b^2)/(c^2 + d^2)`


If (a + ib) (c + id) (e + if) (g + ih) = A + iB, then show that (a2 + b2) (c2 + d2) (e2 + f2) (g2 + h2) = A2 + B2.


Write the conjugates of the following complex number:

`-sqrt(5) - sqrt(7)"i"`


Write the conjugates of the following complex number:

`-sqrt(-5)`


Find the value of i + i2 + i3 + i4 


Simplify : `("i"^592 + "i"^590 + "i"^588 + "i"^586 + "i"^584)/("i"^582 + "i"^580 + "i"^578 + "i"^576 + "i"^574)`


If a = `(-1 + sqrt(3)"i")/2`, b = `(-1 - sqrt(3)"i")/2` then show that a2 = b and b2 = a


If x + iy = (a + ib)3, show that `x/"a" + y/"b"` = 4(a2 − b2)


Show that `((sqrt(7) + "i"sqrt(3))/(sqrt(7) - "i"sqrt(3)) + (sqrt(7) - "i"sqrt(3))/(sqrt(7) + "i"sqrt(3)))` is real


Find the value of x and y which satisfy the following equation (x, y∈R).

`(x+ 1)/(1 + "i") + (y - 1)/(1 - "i")` = i


Find the value of x and y which satisfy the following equation (x, y∈R).

If x(1 + 3i) + y(2 − i) − 5 + i3 = 0, find x + y


Answer the following:

Solve the following equation for x, y ∈ R:

(4 − 5i)x + (2 + 3i)y = 10 − 7i


Answer the following:

Solve the following equations for x, y ∈ R:

(x + iy) (5 + 6i) = 2 + 3i


Solve the following equation for x, y ∈ R:

2x + i9y (2 + i) = xi7 + 10i16


Answer the following:

Evaluate: (1 − i + i2)−15 


Answer the following:

Evaluate: i131 + i49 


Answer the following:

Simplify: `("i"^29 + "i"^39 + "i"^49)/("i"^30 + "i"^40 + "i"^50)`


Answer the following:

Simplify: `("i"^238 + "i"^236 + "i"^234 + "i"^232 + "i"^230)/("i"^228 + "i"^226 + "i"^224 + "i"^222 + "i"^220)`


If |z1| = 1, |z2| = 2, |z3| = 3 and |9z1z2 + 4z1z3 + z2z3| = 12, then the value of |z1 + z2 + z3| is


If z1, z2, z3 are complex numbers such that `|z_1| = |z_2| = |z_3| = |1/z_1 + 1/z_2 + 1/z_3|` = 1, then find the value of |z1 + z2 + z3|.


Find the value of 2x4 + 5x3 + 7x2 – x + 41, when x = `-2 - sqrt(3)"i"`.


Find the value of k if for the complex numbers z1 and z2, `|1 - barz_1z_2|^2 - |z_1 - z_2|^2 = k(1 - |z_1|^2)(1 - |"z"_2|^2)`


State true or false for the following:

If n is a positive integer, then the value of in + (i)n+1 + (i)n+2 + (i)n+3 is 0.


If the complex number z = x + iy satisfies the condition |z + 1| = 1, then z lies on ______.


If the real part of `(barz + 2)/(barz - 1)` is 4, then show that the locus of the point representing z in the complex plane is a circle.


Solve the equation |z| = z + 1 + 2i.


If |z1| = 1(z1 ≠ –1) and z2 = `(z_1 - 1)/(z_1 + 1)`, then show that the real part of z2 is zero.


State True or False for the following:

For any complex number z the minimum value of |z| + |z – 1| is 1.


State True or False for the following:

The locus represented by |z – 1| = |z – i| is a line perpendicular to the join of (1, 0) and (0, 1).


Where does z lie, if `|(z - 5i)/(z + 5i)|` = 1.


If a complex number z satisfies the equation `z + sqrt(2)|z + 1| + i` = 0, then |z| is equal to ______.


If α, β, γ and a, b, c are complex numbers such that `α/a +  β/b + γ/c` = 1 + i and `a/α +  b/β + c/γ` = 0, then the value of `α^2/a^2 +  β^2/b^2 + γ^2/c^2` is equal to ______.


If `|(6i, -3i, 1),(4, 3i, -1),(20, 3, i)|` = x + iy, then ______.


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

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


Show that `(-1 + sqrt3 i)^3` is a real number.


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

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


Evaluate the following:

i35


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×