Answer:
308[cos(45) + isin(45)]
Step-by-step explanation:
z1×z2:
Modulus: r1 × r2
= 7×44 = 308
Argument: theta1 + theta2
= -70 + 115 = 45
z1z2 = 308[cos(45) + isin(45)]
Or
z1z2 = 154sqrt(2) + (i)154sqrt(2)
sqrt: square root
Answer:
On a coordinate plane, a triangle has points (negative 4, 3), (negative 4, negative 2), (1, negative 2).
Step-by-step explanation:
The points (-4,3), (1,2) and (-4, -2) would form a right triangle when graphed and connected by lines.
(-4,3), (1,2) and (1,3) would also work as well
Step-by-step explanation:
B. One of the graphs is positioned 4 units lower than the other.
(as the drawing attached)
First term ,a=4 , common difference =4-7=-3, n =50
sum of first 50terms= (50/2)[2×4+(50-1)(-3)]
=25×[8+49]×-3
=25×57×-3
=25× -171
= -42925
derivation of the formula for the sum of n terms
Progression, S
S=a1+a2+a3+a4+...+an
S=a1+(a1+d)+(a1+2d)+(a1+3d)+...+[a1+(n−1)d] → Equation (1)
S=an+an−1+an−2+an−3+...+a1
S=an+(an−d)+(an−2d)+(an−3d)+...+[an−(n−1)d] → Equation (2)
Add Equations (1) and (2)
2S=(a1+an)+(a1+an)+(a1+an)+(a1+an)+...+(a1+an)
2S=n(a1+an)
S=n/2(a1+an)
Substitute an = a1 + (n - 1)d to the above equation, we have
S=n/2{a1+[a1+(n−1)d]}
S=n/2[2a1+(n−1)d]