Answer:
-8i
Step-by-step explanation:
To multiply numbers is polar form
z1 = r1 ( cos theta 1 + i sin theta 1)
z2 = r2 ( cos theta 2 + i sin theta 2)
z1*z2 = r1*r2 (cos (theta1+theta2) + i sin (theta1+theta2)
z1 = 2(cos 70° + i sin 70°)
z2 = 4(cos 200+ i sin 200)
z1z2 = 2*4 (cos (70+200) + i sin (70+200)
z1z2 = 8 (cos(270) + i sin (270))
= 8 (0 + i (-1))
=-8i
Answer:
-63
Step-by-step explanation:
(-25+4^2) * 7
(-25+16) * 7
-9*7=-63
3rd one 10 x 6 x 6
hope this is right
Answer:
C
Step-by-step explanation:
transposition
3x/4=1/5
xc=yc
15x/20×20=4/20×20
15x=4
x=4/15