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In Spanish, how do we know whether to use the preterite tense or the imperfect tense?

To start with, the preterite is used in two main cases: is the tense which you use to say (1) what you did or (2) what happened . To form the preterite of regular verbs, remove the –ar, –er or –ir from the i...
RD
Answered by Rocio D. • Spanish tutor
2670 Views

find all the roots to the equation: z^3 = 1 + i in polar form

1st write 1+ i in polar form, sketch a diagram to find the angle ( =pi/4) and find the modulus ( sqrt(2))z^3 = Sqrt(2) E^ipi/4This is true for all equivalent solutions (add 2kpi) z^3 = sqrt(2)e^(pi/4 +2kpi)i...
RM
11276 Views

How do I know which out of the Sine and Cosine rule I should use?

If you look at the formulae for the Sine and Cosine rules you'll see that the Sine rule involves two angles and two sides and the Cosine rule involves one angle and three sides.So have a look at the problem ...
JH
Answered by Julian H. • Maths tutor
5768 Views

Find an expression in terms of powers of cos(x) for cos(5x)

De Moivre's theorem states that e ix = cos(x) + isin(x) or that e i5x = cos(5x)+ isin(5x). If the real components of both sides of this equation is taken we can see that : cos(5x) = Re[e i5x ] where Re means...
AA
Answered by Arnav A. • Maths tutor
7934 Views

What is the difference between Reverse osmosis and osmosis?

Osmosis is a natural phenomenon where the water molecules will seep through the semipermeable membrane separating 2 compartments, from an area of lower concentration to the area of higher concentration until...
KK
8886 Views