(0,-1)(1,0)(2,3)(3,8)(4,15)
Recall that 2sin(x) cos(x) is actually equal to sin(2x).
We can prove this by expanding sin(2x) to sin(x + x).
sin(x + x) = sin(x) cos(x) + cos(x) sin(x) = 2sinxcosx
Thus, 2sin(x/2)cos(x/2) can be rewritten in the form:
sin(2x/2), and this simplifies down to sinx.
Answer:
3. 18 + 18 + 7 + 7 = 50
4. 120 degrees
Step-by-step explanation:
Answer:
b=2
Step-by-step explanation:
we have
9x+12y=21 -----> equation A
6x+8y=7b ----> equation B
we know that
If the system of equations have an infinite number of solutions then the equation A must be equal to the equation B
Multiply equation B by 1.5 both sides
1.5*[6x+8y[=7b*1.5
9x+12y=10.5b ----> equation C
Compare equation A and equation C
9x+12y=21 -----> equation A
9x+12y=10.5b ----> equation C
For the equations to be equal it must be fulfilled that
21=10.5b
solve for b
b=21/10.5
b=2
