Answer:
122˚
Step-by-step explanation:
1. Visual estimation
∠BXD is obtuse so ∠BXD > 90˚
Answer:
You know that if f(x) = 1/(x²+1) then F(x)=arctan(x).
What is arctan(x) function? It is inverse function of tan(x) in tge range (-π/2, π/2).
So if tan(x) = y then x = arctan(y)
therefore arctan(-1) = -π/4 because tan(-π/4)=-1 and arctan(1)=π/4 because tan(π/4) = 1.
In conclusion:
integral (dx/(x²+1)) from -1 to 1 =
= F(1) - F(-1) = arctan(1) - arctan(-1) =
=π/4-(-π/4)=π/4+π/4 = π/2.
answer B is correct
Mode, because it is the measure that occurs most often
Arc length = angle (in rad!!) * radius:
45 degree = pi / 4 rad
Arc length = pi/ 4 * 15 = 15/4*pi feet or approx. 11.781 feet
Also in this case only, 45 degrees is 1/8 of the whole circle, so Arc length = 2pir/8 = pi/4*r, but only this case. the first formula always works!
X^2 + 14x + 17 = -96
x^2 + 14x + 113 = 0
x^2 + 14x + 49 + 64 = 0
(x + 7)^2 = -64
x + 7 = sqrt(-64) = + or - 8i
x = -7 + or - 8i
