We know that
2π/3 radians-------> convert to degrees-----> 2*180/3---> 120°
120°=90°+30°
Part a) Find <span>sin(2π/3)
</span>sin(2π/3)=sin (90°+30°)
we know that
sin (A+B)=sin A*cos B+cos A*sin B
so
sin (90°+30°)=sin 90*cos 30+cos 90*sin 30
sin 90=1
cos 30=√3/2
cos 90=0
sin 30=1/2
sin (90°+30°)=1*√3/2+0*1/2-----> √3/2
the answer part a) is
sin(2π/3)=√3/2
Part b) Find cos (2π/3)
cos (2π/3)=cos (90°+30°)
we know that
cos (A+B)=cos A*cos B-sin A*sin B
so
cos (90°+30°)=cos 90*cos 30-sin 90*sin 30
sin 90=1
cos 30=√3/2
cos 90=0
sin 30=1/2
cos (90°+30°)=0*√3/2-1*1/2----> -1/2
the answer part b) is
cos (2π/3)=-1/2
Answer:
all the points below this line towards (0, 0) on the whole plain will work
Step-by-step explanation:
This line passes through (0, 2) and (-4, 0) which puts it in the fourth quadrant
y < 0.5x + 2 i.e. 0 < 2 which is true
all the points below this line towards (0, 0) on the whole plain will work
4 10/8 breaks down to 5 2/8 = 5 1/4
3 1/2 + 1 3/4
3 1/2 = 3 2/4
3 2/4 + 1 3/4 = 4 5/4
the correct answer is 5 1/4
so yes, your answer IS correct!
Answer:
B
Step-by-step explanation:
12x² - 157x - 40
Consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term
product = 12 × - 40 = - 480 and sum = - 157
The factors are + 3 and - 160
Use these factors to split the x- term
12x² + 3x - 160x - 40 ( factor the first/second and third/fourth terms
= 3x(4x + 1) - 40(4x + 1) ← factor out (4x + 1) from each term
= (4x + 1)(3x - 40) ← in factored form → B