Answer:
16
Step-by-step explanation:
Let the 1st part of your answer be x
, so the 2nd part will be 40-x
. From the given information, we can write the equation: (1/4)x = (3/8) × (40-x)
. We can simplify this into (1/4)x = (120-3x)/8
; 8x = 480-12x
; 8x+12x = 480
; 20x = 480
; x = 480/20; x = 24
Therefore, the 1st part = 24
Plug this into your 40-x equation to get: 40 - 24 = 16
Divide 83.524 by pi then take half of that answer .
the answer should be 13.29 or 13.3
Hello here is a solution:
Since sin(2x)=2sinxcosx, we can plug that in to get sin(4x)=2sin(2x)cos(2x)=2*2sinxcosxcos(2x)=4sinxcosxcos(2x). Since cos(2x) = cos^2x-sin^2x, we plug that in. In addition, cos4x=cos^2(2x)-sin^2(2x). Next, since cos^2x=(1+cos(2x))/2 and sin^2x= (1-cos(2x))/2, we plug those in to end up with 4sinxcosxcos(2x)-((1+cos(2x))/2-(1-cos(2x))/2)
=4sinxcosxcos(2x)-(2cos(2x)/2)=4sinxcosxcos(2x)-cos(2x)
=cos(2x)*(4sinxcosx-1). Since sinxcosx=sin(2x), we plug that back in to end up with cos(2x)*(4sin(2x)-1)
