The complex number -7i into trigonometric form is 7 (cos (90) + sin (90) i) and 3 + 3i in trigonometric form is 4.2426 (cos (45) + sin (45) i)
<h3>What is a complex number?</h3>
It is defined as the number which can be written as x+iy where x is the real number or real part of the complex number and y is the imaginary part of the complex number and i is the iota which is nothing but a square root of -1.
We have a complex number shown in the picture:
-7i(3 + 3i)
= -7i
In trigonometric form:
z = 7 (cos (90) + sin (90) i)
= 3 + 3i
z = 4.2426 (cos (45) + sin (45) i)




=21-21i
After converting into the exponential form:

From part (b) and part (c) both results are the same.
Thus, the complex number -7i into trigonometric form is 7 (cos (90) + sin (90) i) and 3 + 3i in trigonometric form is 4.2426 (cos (45) + sin (45) i)
Learn more about the complex number here:
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Covert the problem into and equation using formulas
Answer:
x^3+3x^2+9x+27
Step-by-step explanation:

_____
The factoring of the difference of squares is used (twice):
a² -b² = (a -b)(a +b)
Tienes que usar la fórmula cuadrática:
(-b +/- √(b^2-4ac))/2a
Primero identificas los valores de a,b y c en kx^2-3x+2=0
K=a, b=-3, c=2
Luego sustituis en la fórmula y te queda:
(3+/-√(9-8k))/2k
Para que las raíces Sena reales se tienen que cumplir que 9-8k>=0
Answer:
79.25
Step-by-step explanation: