Trigonometry Examples
-27√22+27√22i−27√22+27√22i , n=3n=3
Step 1
Calculate the distance from (a,b)(a,b) to the origin using the formula r=√a2+b2r=√a2+b2.
r=√(-27√22)2+(27√22)2r=
⎷(−27√22)2+(27√22)2
Step 2
Step 2.1
Use the power rule (ab)n=anbn(ab)n=anbn to distribute the exponent.
Step 2.1.1
Apply the product rule to -27√22−27√22.
r=√(-1)2(27√22)2+(27√22)2r=
⎷(−1)2(27√22)2+(27√22)2
Step 2.1.2
Apply the product rule to 27√2227√22.
r=√(-1)2(27√2)222+(27√22)2r=
⎷(−1)2(27√2)222+(27√22)2
Step 2.1.3
Apply the product rule to 27√227√2.
r=√(-1)2272√2222+(27√22)2r=
⎷(−1)2272√2222+(27√22)2
r=√(-1)2272√2222+(27√22)2r=
⎷(−1)2272√2222+(27√22)2
Step 2.2
Simplify the expression.
Step 2.2.1
Raise -1−1 to the power of 22.
r=√1272√2222+(27√22)2r=
⎷1272√2222+(27√22)2
Step 2.2.2
Multiply 272√2222272√2222 by 11.
r=√272√2222+(27√22)2r=
⎷272√2222+(27√22)2
r=√272√2222+(27√22)2r=
⎷272√2222+(27√22)2
Step 2.3
Simplify the numerator.
Step 2.3.1
Raise 2727 to the power of 22.
r=√729√2222+(27√22)2r=
⎷729√2222+(27√22)2
Step 2.3.2
Rewrite √22√22 as 22.
Step 2.3.2.1
Use n√ax=axnn√ax=axn to rewrite √2√2 as 212212.
r=√729(212)222+(27√22)2r=
⎷729(212)222+(27√22)2
Step 2.3.2.2
Apply the power rule and multiply exponents, (am)n=amn(am)n=amn.
r=√729⋅212⋅222+(27√22)2r=
⎷729⋅212⋅222+(27√22)2
Step 2.3.2.3
Combine 12 and 2.
r=√729⋅22222+(27√22)2
Step 2.3.2.4
Cancel the common factor of 2.
Step 2.3.2.4.1
Cancel the common factor.
r=√729⋅22222+(27√22)2
Step 2.3.2.4.2
Rewrite the expression.
r=√729⋅2122+(27√22)2
r=√729⋅2122+(27√22)2
Step 2.3.2.5
Evaluate the exponent.
r=√729⋅222+(27√22)2
r=√729⋅222+(27√22)2
r=√729⋅222+(27√22)2
Step 2.4
Reduce the expression by cancelling the common factors.
Step 2.4.1
Raise 2 to the power of 2.
r=√729⋅24+(27√22)2
Step 2.4.2
Multiply 729 by 2.
r=√14584+(27√22)2
Step 2.4.3
Cancel the common factor of 1458 and 4.
Step 2.4.3.1
Factor 2 out of 1458.
r=√2(729)4+(27√22)2
Step 2.4.3.2
Cancel the common factors.
Step 2.4.3.2.1
Factor 2 out of 4.
r=√2⋅7292⋅2+(27√22)2
Step 2.4.3.2.2
Cancel the common factor.
r=√2⋅7292⋅2+(27√22)2
Step 2.4.3.2.3
Rewrite the expression.
r=√7292+(27√22)2
r=√7292+(27√22)2
r=√7292+(27√22)2
r=√7292+(27√22)2
Step 2.5
Use the power rule (ab)n=anbn to distribute the exponent.
Step 2.5.1
Apply the product rule to 27√22.
r=√7292+(27√2)222
Step 2.5.2
Apply the product rule to 27√2.
r=√7292+272√2222
r=√7292+272√2222
Step 2.6
Simplify the numerator.
Step 2.6.1
Raise 27 to the power of 2.
r=√7292+729√2222
Step 2.6.2
Rewrite √22 as 2.
Step 2.6.2.1
Use n√ax=axn to rewrite √2 as 212.
r=√7292+729(212)222
Step 2.6.2.2
Apply the power rule and multiply exponents, (am)n=amn.
r=√7292+729⋅212⋅222
Step 2.6.2.3
Combine 12 and 2.
r=√7292+729⋅22222
Step 2.6.2.4
Cancel the common factor of 2.
Step 2.6.2.4.1
Cancel the common factor.
r=√7292+729⋅22222
Step 2.6.2.4.2
Rewrite the expression.
r=√7292+729⋅2122
r=√7292+729⋅2122
Step 2.6.2.5
Evaluate the exponent.
r=√7292+729⋅222
r=√7292+729⋅222
r=√7292+729⋅222
Step 2.7
Reduce the expression by cancelling the common factors.
Step 2.7.1
Raise 2 to the power of 2.
r=√7292+729⋅24
Step 2.7.2
Multiply 729 by 2.
r=√7292+14584
Step 2.7.3
Cancel the common factor of 1458 and 4.
Step 2.7.3.1
Factor 2 out of 1458.
r=√7292+2(729)4
Step 2.7.3.2
Cancel the common factors.
Step 2.7.3.2.1
Factor 2 out of 4.
r=√7292+2⋅7292⋅2
Step 2.7.3.2.2
Cancel the common factor.
r=√7292+2⋅7292⋅2
Step 2.7.3.2.3
Rewrite the expression.
r=√7292+7292
r=√7292+7292
r=√7292+7292
Step 2.7.4
Simplify the expression.
Step 2.7.4.1
Combine the numerators over the common denominator.
r=√729+7292
Step 2.7.4.2
Add 729 and 729.
r=√14582
Step 2.7.4.3
Divide 1458 by 2.
r=√729
Step 2.7.4.4
Rewrite 729 as 272.
r=√272
Step 2.7.4.5
Pull terms out from under the radical, assuming positive real numbers.
r=27
r=27
r=27
r=27
Step 3
Calculate reference angle θ̂=arctan(|ba|).
θ̂=arctan(|27√22-27√22|)
Step 4
Step 4.1
Cancel the common factor of 27√22.
Step 4.1.1
Cancel the common factor.
θ̂=arctan(|27√22-27√22|)
Step 4.1.2
Rewrite the expression.
θ̂=arctan(|1-1|)
Step 4.1.3
Move the negative one from the denominator of 1-1.
θ̂=arctan(|-1⋅1|)
θ̂=arctan(|-1⋅1|)
Step 4.2
Multiply -1 by 1.
θ̂=arctan(|-1|)
Step 4.3
The absolute value is the distance between a number and zero. The distance between -1 and 0 is 1.
θ̂=arctan(1)
Step 4.4
The exact value of arctan(1) is π4.
θ̂=π4
θ̂=π4
Step 5
The point is located in the second quadrant because x is negative and y is positive. The quadrants are labeled in counter-clockwise order, starting in the upper-right.
Quadrant 2
Step 6
(a,b) is in the second quadrant. θ=π-θ̂
θ=π-π4
Step 7
Step 7.1
To write π as a fraction with a common denominator, multiply by 44.
π⋅44-π4
Step 7.2
Combine fractions.
Step 7.2.1
Combine π and 44.
π⋅44-π4
Step 7.2.2
Combine the numerators over the common denominator.
π⋅4-π4
π⋅4-π4
Step 7.3
Simplify the numerator.
Step 7.3.1
Move 4 to the left of π.
4⋅π-π4
Step 7.3.2
Subtract π from 4π.
3π4
3π4
3π4
Step 8
Use the formula to find the roots of the complex number.
(a+bi)1n=r1ncis(θ+2πkn), k=0,1,…,n-1
Step 9
Step 9.1
To write π as a fraction with a common denominator, multiply by 44.
(27)13cisπ⋅44-π4+2πk3
Step 9.2
Combine π and 44.
(27)13cisπ⋅44-π4+2πk3
Step 9.3
Combine the numerators over the common denominator.
(27)13cisπ⋅4-π4+2πk3
Step 9.4
Subtract π from π⋅4.
Step 9.4.1
Reorder π and 4.
(27)13cis4⋅π-π4+2πk3
Step 9.4.2
Subtract π from 4⋅π.
(27)13cis3⋅π4+2πk3
(27)13cis3⋅π4+2πk3
Step 9.5
Combine (27)13 and 3⋅π4+2πk3.
cis(27)13(3⋅π4+2πk)3
Step 9.6
Combine c and (27)13(3⋅π4+2πk)3.
isc((27)13(3⋅π4+2πk))3
Step 9.7
Combine i and c((27)13(3⋅π4+2πk))3.
si(c((27)13(3⋅π4+2πk)))3
Step 9.8
Combine s and i(c((27)13(3⋅π4+2πk)))3.
s(i(c((27)13(3⋅π4+2πk))))3
Step 9.9
Remove parentheses.
Step 9.9.1
Remove parentheses.
s(i(c(2713(3⋅π4+2πk))))3
Step 9.9.2
Remove parentheses.
s(i(c⋅2713(3⋅π4+2πk)))3
Step 9.9.3
Remove parentheses.
s(i(c⋅2713)(3⋅π4+2πk))3
Step 9.9.4
Remove parentheses.
s(ic⋅2713(3⋅π4+2πk))3
Step 9.9.5
Remove parentheses.
s(ic⋅2713)(3⋅π4+2πk)3
Step 9.9.6
Remove parentheses.
s(ic)⋅2713(3⋅π4+2πk)3
Step 9.9.7
Remove parentheses.
sic⋅2713(3⋅π4+2πk)3
sic⋅2713(3⋅π4+2πk)3
sic⋅2713(3⋅π4+2πk)3
Step 10
Step 10.1
Rewrite 27 as 33.
k=0:(33)13cis((π-π4)+2π(0)3)
Step 10.2
Apply the power rule and multiply exponents, (am)n=amn.
k=0:33(13)cis((π-π4)+2π(0)3)
Step 10.3
Cancel the common factor of 3.
Step 10.3.1
Cancel the common factor.
k=0:33(13)cis((π-π4)+2π(0)3)
Step 10.3.2
Rewrite the expression.
k=0:3cis((π-π4)+2π(0)3)
k=0:3cis((π-π4)+2π(0)3)
Step 10.4
Evaluate the exponent.
k=0:3cis((π-π4)+2π(0)3)
Step 10.5
To write π as a fraction with a common denominator, multiply by 44.
k=0:3cis(π⋅44-π4+2π(0)3)
Step 10.6
Combine π and 44.
k=0:3cis(π⋅44-π4+2π(0)3)
Step 10.7
Combine the numerators over the common denominator.
k=0:3cis(π⋅4-π4+2π(0)3)
Step 10.8
Simplify the numerator.
Step 10.8.1
Move 4 to the left of π.
k=0:3cis(4⋅π-π4+2π(0)3)
Step 10.8.2
Subtract π from 4π.
k=0:3cis(3π4+2π(0)3)
k=0:3cis(3π4+2π(0)3)
Step 10.9
Multiply 2π(0).
Step 10.9.1
Multiply 0 by 2.
k=0:3cis(3π4+0π3)
Step 10.9.2
Multiply 0 by π.
k=0:3cis(3π4+03)
k=0:3cis(3π4+03)
Step 10.10
Add 3π4 and 0.
k=0:3cis(3π43)
Step 10.11
Multiply the numerator by the reciprocal of the denominator.
k=0:3cis(3π4⋅13)
Step 10.12
Cancel the common factor of 3.
Step 10.12.1
Factor 3 out of 3π.
k=0:3cis(3(π)4⋅13)
Step 10.12.2
Cancel the common factor.
k=0:3cis(3π4⋅13)
Step 10.12.3
Rewrite the expression.
k=0:3cis(π4)
k=0:3cis(π4)
k=0:3cis(π4)
Step 11
Step 11.1
Rewrite 27 as 33.
k=1:(33)13cis((π-π4)+2π(1)3)
Step 11.2
Apply the power rule and multiply exponents, (am)n=amn.
k=1:33(13)cis((π-π4)+2π(1)3)
Step 11.3
Cancel the common factor of 3.
Step 11.3.1
Cancel the common factor.
k=1:33(13)cis((π-π4)+2π(1)3)
Step 11.3.2
Rewrite the expression.
k=1:3cis((π-π4)+2π(1)3)
k=1:3cis((π-π4)+2π(1)3)
Step 11.4
Evaluate the exponent.
k=1:3cis((π-π4)+2π(1)3)
Step 11.5
To write π as a fraction with a common denominator, multiply by 44.
k=1:3cis(π⋅44-π4+2π(1)3)
Step 11.6
Combine π and 44.
k=1:3cis(π⋅44-π4+2π(1)3)
Step 11.7
Combine the numerators over the common denominator.
k=1:3cis(π⋅4-π4+2π(1)3)
Step 11.8
Simplify the numerator.
Step 11.8.1
Move 4 to the left of π.
k=1:3cis(4⋅π-π4+2π(1)3)
Step 11.8.2
Subtract π from 4π.
k=1:3cis(3π4+2π(1)3)
k=1:3cis(3π4+2π(1)3)
Step 11.9
Multiply 2 by 1.
k=1:3cis(3π4+2π3)
Step 11.10
To write 2π as a fraction with a common denominator, multiply by 44.
k=1:3cis(3π4+2π⋅443)
Step 11.11
Combine 2π and 44.
k=1:3cis(3π4+2π⋅443)
Step 11.12
Combine the numerators over the common denominator.
k=1:3cis(3π+2π⋅443)
Step 11.13
Simplify the numerator.
Step 11.13.1
Multiply 4 by 2.
k=1:3cis(3π+8π43)
Step 11.13.2
Add 3π and 8π.
k=1:3cis(11π43)
k=1:3cis(11π43)
Step 11.14
Multiply the numerator by the reciprocal of the denominator.
k=1:3cis(11π4⋅13)
Step 11.15
Multiply 11π4⋅13.
Step 11.15.1
Multiply 11π4 by 13.
k=1:3cis(11π4⋅3)
Step 11.15.2
Multiply 4 by 3.
k=1:3cis(11π12)
k=1:3cis(11π12)
k=1:3cis(11π12)
Step 12
Step 12.1
Rewrite 27 as 33.
k=2:(33)13cis((π-π4)+2π(2)3)
Step 12.2
Apply the power rule and multiply exponents, (am)n=amn.
k=2:33(13)cis((π-π4)+2π(2)3)
Step 12.3
Cancel the common factor of 3.
Step 12.3.1
Cancel the common factor.
k=2:33(13)cis((π-π4)+2π(2)3)
Step 12.3.2
Rewrite the expression.
k=2:3cis((π-π4)+2π(2)3)
k=2:3cis((π-π4)+2π(2)3)
Step 12.4
Evaluate the exponent.
k=2:3cis((π-π4)+2π(2)3)
Step 12.5
To write π as a fraction with a common denominator, multiply by 44.
k=2:3cis(π⋅44-π4+2π(2)3)
Step 12.6
Combine π and 44.
k=2:3cis(π⋅44-π4+2π(2)3)
Step 12.7
Combine the numerators over the common denominator.
k=2:3cis(π⋅4-π4+2π(2)3)
Step 12.8
Simplify the numerator.
Step 12.8.1
Move 4 to the left of π.
k=2:3cis(4⋅π-π4+2π(2)3)
Step 12.8.2
Subtract π from 4π.
k=2:3cis(3π4+2π(2)3)
k=2:3cis(3π4+2π(2)3)
Step 12.9
Multiply 2 by 2.
k=2:3cis(3π4+4π3)
Step 12.10
To write 4π as a fraction with a common denominator, multiply by 44.
k=2:3cis(3π4+4π⋅443)
Step 12.11
Combine 4π and 44.
k=2:3cis(3π4+4π⋅443)
Step 12.12
Combine the numerators over the common denominator.
k=2:3cis(3π+4π⋅443)
Step 12.13
Simplify the numerator.
Step 12.13.1
Multiply 4 by 4.
k=2:3cis(3π+16π43)
Step 12.13.2
Add 3π and 16π.
k=2:3cis(19π43)
k=2:3cis(19π43)
Step 12.14
Multiply the numerator by the reciprocal of the denominator.
k=2:3cis(19π4⋅13)
Step 12.15
Multiply 19π4⋅13.
Step 12.15.1
Multiply 19π4 by 13.
k=2:3cis(19π4⋅3)
Step 12.15.2
Multiply 4 by 3.
k=2:3cis(19π12)
k=2:3cis(19π12)
k=2:3cis(19π12)
Step 13
List the solutions.
k=0:3cis(π4)
k=1:3cis(11π12)
k=2:3cis(19π12)