Well, the keyword here is One of the performers insist on being the last.
So, the amount of performers that we can arrange freely is 7 performers.
Different ways we can schedule their appearance is :
7 ! = 7 x 6 x 5 x 4 x 3 x 2 x 1
= 5040
hope this helps
Answer:
In mathematics, the dot product or scalar product is an algebraic operation that takes two equal-length sequences of numbers (usually coordinate vectors), and returns a single number. ... Algebraically, the dot product is the sum of the products of the corresponding entries of the two sequences of numbers
kamsahamnida have a great day
Answer: 31
How: If there are two negative signs like this, you would connect them together and make it into a addition sign where you then can add them.
In Δ ABC, ∠A=120°, AB=AC=1
To draw a circumscribed circle Draw perpendicular bisectors of any of two sides.The point where these bisectors meet is the center of the circle.Mark the center as O.
Then join OA, OB, and OC.
Taking any one OA,OB and OC as radius draw the circumcircle.
Now, from O Draw OM⊥AB and ON⊥AC.
As chord AB and AC are equal,So OM and ON will also be equal.
The reason being that equal chords are equidistant from the center.
AM=MB=1/2 and AN=NC=1/2 [ perpendicular from the center to the chord bisects the chord.]
In Δ OMA and ΔONA
OM=ON [proved above]
OA is common.
MA=NA=1/2 [proved above]
ΔOMA≅ ONA [SSS]
∴ ∠OAN =∠OAM=60° [ CPCT]
In Δ OAN


OA=1
∴ OA=OB=OC=1, which is the radius of given Circumscribed circle.