Question
Simplify the expression
cos(43π)+isin(43π)cos(47π)+isin(47π)
Alternative Form
−22+22i22−22i
Evaluate
−i
Rewrite the complex number in polar form
More Steps

Evaluate
−i
Determine the modulus and the argument of the complex number
r=02+(−1)2θ=arctan(0−1)
Calculate
More Steps

Evaluate
02+(−1)2
Calculate
0+(−1)2
Evaluate the power
0+1
Removing 0 doesn't change the value,so remove it from the expression
1
Simplify the root
1
r=1θ=arctan(0−1)
Substitute the given values into the formula r(cosθ+isinθ)
1×(cos(23π)+isin(23π))
1×(cos(23π)+isin(23π))
Calculate the nth roots of a complex r(cos(θ)+i×sin(θ),using nz=nr(cosnθ+2kπ+isinnθ+2kπ)
1×(cos(223π+2kπ)+isin(223π+2kπ))
Simplify
1×(cos(223π+2kπ)+isin(223π+2kπ))
Simplify
cos(223π+2kπ)+isin(223π+2kπ)
Since n=2,substitute k=0,1 into the expression
cos(223π+2×0×π)+isin(223π+2×0×π)cos(223π+2×1×π)+isin(223π+2×1×π)
Calculate
More Steps

Evaluate
223π+2×0×π
Any expression multiplied by 0 equals 0
223π+0
Removing 0 doesn't change the value,so remove it from the expression
223π
Multiply by the reciprocal
23π×21
To multiply the fractions,multiply the numerators and denominators separately
2×23π
Multiply the numbers
43π
cos(43π)+isin(43π)cos(223π+2×1×π)+isin(223π+2×1×π)
Solution
More Steps

Evaluate
223π+2×1×π
Multiply the terms
223π+2π
Calculate
More Steps

Evaluate
23π+2π
Reduce fractions to a common denominator
23π+22π×2
Write all numerators above the common denominator
23π+2π×2
Multiply the terms
23π+4π
Add the numbers
27π
227π
Multiply by the reciprocal
27π×21
To multiply the fractions,multiply the numerators and denominators separately
2×27π
Multiply the numbers
47π
cos(43π)+isin(43π)cos(47π)+isin(47π)
Alternative Form
−22+22i22−22i
Show Solution
