Which of the following equations correctly represnt the law of cosines? a. b2 = a2 + b2 – 2ab ⋅ cos(c) b. c2 = a2 + b2 – 2ab ⋅ cos(b) c. b2 = a2 + c2 – 2ac ⋅ cos(b) d. a2 = b2 + c2 – 2ac ⋅ cos(a)

law of cosines

c^2=a^2+b^2-2abcosC

b^2=a^2+c^2-2accosB

a^2=b^2+c^2-2bccosA  

Choice C

f(2x−x2)=−3x2+6x−1

step-by-step explanation:

set up the composite function and evaluate.

f(2x−x2)=−3x2+6x−1

option 2 is correct.

step-by-step explanation:

we are given two inequality equation

x+y> 5 and -3x+2y< -2

first we draw the graph of both function using t-table method

equation: x+y> 5

for x=0, y=5

for x=-5, y=0

table:

x   :   0     5

y   :   5     0

test point (0,0) , 0> 5

false

equation: -3x+2y< -2

for x=0, y=-1

for x=2, y=4

table:

x   :   0     2

y   : -1       4

test point (0,0) , 0< -2

true

now we draw the graph. see the attachment for graph.

common region would be solution set.

option 2 is correct.