Answer:
answer is : Cos(13pi/8) = 0.3826
Step-by-step explanation:
We have, Cos (13pi/8)
Since 13pi/8 can be shown as 3pi/2 < 13pi/8 < 2pi
Hence 13pi/8 lies on fourth quadrant.
In fourth quadrant cosine will be positive.
Cos (13pi/8) = cos(3pi/2 + pi/8)
applying formula cos(A+B) = cos A cosB - sinAsinB
i.e Cos(3pi/2 + pi/8) = cos(3pi/2)cos(pi/8) - sin(3pi/2)sin(pi/8)
∵ Remember cos(3pi/2) =0 , sin(3pi/2) = -1
Cos(3pi/2 + pi/8) = 0 cos(pi/8) - (-1)sin(pi/8)
Cos(3pi/2 + pi/8) = 0 + 0.3826
Cos(3pi/2 + pi/8) = 0.3826
Hence we got Cos(13pi/8) = 0.3826
Answer:
-10, -3, 5, 16
Step-by-step explanation:
even though the negative number (10) might seem big, but its not
Answer:
Step-by-step explanation:
Easy way to do this is step by step. Your quadratic, from your entry, must be
.
Step by step looks like this, one thing at a time:
becomes
becomes
and this of course is
Do the same with the subtraction sign to get the other solution.
If you're unsure of how to enter it into your calculator, do it step by step so you don't mess up the sign. If you enter it incorrectly, you could end up with an imaginary number when it should be real, or a real one that should be imaginary.
Just my advice as a high school math teacher.
Question: <span>70% of 120 = ?
Work:
To find what </span><span>70% of 120 is. Do .70 times 120.
.70 x 120 = 84
Final Answer:
84
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