Q. A complex number z1 has a magnitude ∣z1∣=11 and an angle θ1=180∘.Express z1 in rectangular form, as z1=a+bi.Express a+bi in exact terms.z1=□
Conversion formulas: A complex number in polar form can be expressed in rectangular form (a+bi) using the conversion formulasa=r⋅cos(θ) and b=r⋅sin(θ), where r is the magnitude and θ is the angle in radians.
Convert angle to radians: First, we need to convert the angle from degrees to radians. The angle given is 180 degrees, which is equivalent to π radians since 180 degrees ×(π radians /180 degrees) =π radians.
Calculate rectangular form: Now we can use the magnitude ∣z1∣=11 and the angle θ1=π to find the rectangular form. We calculate a=11×cos(π) and b=11×sin(π).
Calculate a: Calculating a gives us a=11×cos(π)=11×(−1)=−11, since cos(π)=−1.
Calculate b: Calculating b gives us b=11×sin(π)=11×0=0, since sin(π)=0.
Final rectangular form: Therefore, the complex number z1 in rectangular form is z1=−11+0i, which simplifies to z1=−11.
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