Q. A complex number z1 has a magnitude ∣z1∣=10 and an angle θ1=210∘.Express z1 in rectangular form, as z1=a+bi.Express a+bi in exact terms.z1=□
Use formula for conversion: To convert a complex number from polar to rectangular form, use the formula z=r(cos(θ)+isin(θ)), where r is the magnitude and θ is the angle.
Plug in values: Given ∣z1∣=10 and θ1=210 degrees, plug these values into the formula.z1=10(cos(210∘)+isin(210∘))
Calculate cosine and sine: Calculate the cosine and sine of 210 degrees. cos(210∘)=−cos(30∘) and sin(210∘)=−sin(30∘) because 210 degrees is in the third quadrant where both sine and cosine are negative.
Use exact values: Use the exact values for cos(30∘) and sin(30∘), which are 23 and 21, respectively.z1=10(−23+i(−21))
Multiply magnitude: Multiply the magnitude 10 by the cosine and sine values to get the rectangular form.z1=10×−3/2+10×i×−1/2
Simplify expression: Simplify the expression to get the final rectangular form. z1=−53+i∗(−5)
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