Answer:
Step-by-step explanation:
You can start by recognizing 19/12π = π +7/12π, so the desired sine is ...
sin(19/12π) = -sin(7/12π) = -(sin(3/12π +4/12π)) = -sin(π/4 +π/3)
-sin(π/4 +π/3) = -sin(π/4)cos(π/3) -cos(π/4)sin(π/3)
Of course, you know that ...
sin(π/4) = cos(π/4) = (√2)/2
cos(π/3) = 1/2
sin(π/3) = (√3)/2
So, the desired value is ...
sin(19π/12) = -(√2)/2×1/2 -(√2)/2×(√3/2) = -(√2)/4×(1 +√3)
Comparing this form to the desired answer form, we see ...
A = 2
B = 3
Answer:
Step-by-step explanation:
13.6
Formula of the sum of the 1st nth term in a Geometric Progression:
Sum = a₁(1-rⁿ)/(1-r), where a₁ = 1st term, r = common ratio and n= rank nth of term (r≠1)
Sum = (-11)[1-(-5⁸)] /[(1-(-5)]
Sum = (-11)(1- 390625)/(6)
SUM = 716,144
Answer:
One solution: x=2.4, y=0.2
Step-by-step explanation:
x-2y=2
y=-2x+5
x-2(-2x+5)=2
x+4x-10=2
5x=2+10=12
x=12:5=2.4
y=-2x+5=-2*2.4+5=-4.8+5=0.2