3 years ago

How do you find an exact value for sin of 40 degrees without using a calculator

1 answer:

8 0

Sin 40° + sin 130° + sin 220° + sin 310° = ...
sin 130° = sin 50°;
sin 220° = - sin 40°;
sin 310° = - sin 50°
... = sin 40° + sin 50° - sin 40° - sin 50° = 0
Answer: 0.

You might be interested in

Easy Question: What is Pi Equal to? A. 12.0 B. 45 C. 3.14 D. 6.32

nataly862011 [7]

It’s easy pi is equal to 3.14 so your answer is c

6 0

3 years ago

How much would Howard Steele need to invest today so that he may withdraw $12,000 each year for the next 20 years, assuming a ra

morpeh [17]

I think its $117,817.20

3 0

3 years ago

The point P(8, 6) is on the terminal side of θ. Evaluate sin θ.

vladimir2022 [97]

Ok so let me help you with this. Here is the procedure:
r² = x² + y² = 8² + 6² = 100
r = 10
x = r cosθ
y = r sinθ
sinθ = y/r = 6/10 = 3/5
Hope this is what you are looking for

3 0

3 years ago

Read 2 more answers

Cost A=0.6489 take the inverse cosine of both sides

Stolb23 [73]

I am not quite sure what the question asks for,
But this is what i assume it wants:

Cos A= 0.6489
In this given one, we basically find the size of the angle A
we do cosine inverse on both sides to get the size of the angle A
$cos^{-1}$ : It looks like this in the calculator
$cos^{-1}$ × cos A= $cos^{-1}$ (0.6489)
( $cos^{-1}$ and cos cancels out)
A= $cos^{-1}$ (0.6489)
A=49.54°
check:
cos 49.54=0.6489 (its right!)

6 0

3 years ago

Please help asap 25 pts

beks73 [17]

$y=ax^2+bx+c\\\\\text{Axis of symmetry:}\ x=\dfrac{-b}{2a}$

$\text{We have:}\\\\y=4x^2+16x-18\\\\a=4;\ b=16;\ c=-18\\\\x=\dfrac{-16}{2\cdot4}=\dfrac{-16}{8}=-2$

Answer: A.

6 0

3 years ago