Recall that
sin(<em>a</em> + <em>b</em>) = sin(<em>a</em>) cos(<em>b</em>) + cos(<em>a</em>) sin(<em>b</em>)
sin(<em>a</em> - <em>b</em>) = sin(<em>a</em>) cos(<em>b</em>) - cos(<em>a</em>) sin(<em>b</em>)
Adding these together gives
sin(<em>a</em> + <em>b</em>) + sin(<em>a</em> - <em>b</em>) = 2 sin(<em>a</em>) cos(<em>b</em>)
To get 14 cos(39<em>x</em>) sin(19<em>x</em>) on the right side, multiply both sides by 7 and replace <em>a</em> = 19<em>x</em> and <em>b</em> = 39<em>x</em> :
7 (sin(19<em>x</em> + 39<em>x</em>) + sin(19<em>x</em> - 39<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
7 (sin(58<em>x</em>) + sin(-20<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
7 (sin(58<em>x</em>) - sin(20<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
True
Step-by-step explanation:
I double checked it I'm positive
Answer: X = t or minus 4 square root 3 and X= 4 square root 3 Explanation: add 48 on both sides bring down x squared = 48 take the square root on both sides you get X= t or - 4 square root 3 and X=4 square root 3) Animex yw
let's bear in mind that B is the midpoint and thus it cuts a segment into two equal halves.
![\bf \underset{\leftarrow \qquad \textit{\large 10x-6}\qquad \to }{\boxed{A}\stackrel{4x+2}{\rule[0.35em]{10em}{0.25pt}} B\stackrel{\underline{4x+2}}{\rule[0.35em]{10em}{0.25pt}\boxed{C}}} \\\\\\ AC=AB+BC\implies 10x-6=(4x+2)+(4x+2)\implies 10x-6=8x+4 \\\\\\ 2x-6=4\implies 2x=10\implies x=\cfrac{10}{2}\implies x= 5 \\\\[-0.35em] ~\dotfill\\\\ AC=(4x+2)+(4x+2)\implies AC=[4(5)+2]+[4(5)+2] \\\\\\ AC=22+22\implies AC=44](https://tex.z-dn.net/?f=%5Cbf%20%5Cunderset%7B%5Cleftarrow%20%5Cqquad%20%5Ctextit%7B%5Clarge%2010x-6%7D%5Cqquad%20%5Cto%20%7D%7B%5Cboxed%7BA%7D%5Cstackrel%7B4x%2B2%7D%7B%5Crule%5B0.35em%5D%7B10em%7D%7B0.25pt%7D%7D%20B%5Cstackrel%7B%5Cunderline%7B4x%2B2%7D%7D%7B%5Crule%5B0.35em%5D%7B10em%7D%7B0.25pt%7D%5Cboxed%7BC%7D%7D%7D%20%5C%5C%5C%5C%5C%5C%20AC%3DAB%2BBC%5Cimplies%2010x-6%3D%284x%2B2%29%2B%284x%2B2%29%5Cimplies%2010x-6%3D8x%2B4%20%5C%5C%5C%5C%5C%5C%202x-6%3D4%5Cimplies%202x%3D10%5Cimplies%20x%3D%5Ccfrac%7B10%7D%7B2%7D%5Cimplies%20x%3D%205%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20AC%3D%284x%2B2%29%2B%284x%2B2%29%5Cimplies%20AC%3D%5B4%285%29%2B2%5D%2B%5B4%285%29%2B2%5D%20%5C%5C%5C%5C%5C%5C%20AC%3D22%2B22%5Cimplies%20AC%3D44)
Answer:
x = 15
Step-by-step explanation:
Assuming 3x and x-60 are in degrees, you can use:
cos(a) = sin(a+90)
To rewrite the equation as:
sin(3x) = sin(x-60+90)
sin(3x) = sin(x+30)
3x = x+30
2x = 30
x = 15
But, solving 3x = x+30 which simplifies to x=15 is not the only solution to this equation, as you can see in below picture. Finding all solutions is a bit more work, but maybe that is not required in your case.