<span>sinx - cosx =sqrt(2)
Taking square on both sides:
</span>(sinx - cosx)^2 =sqrt(2)^2<span>
sin^2(x) -2cos(x)sin(x) + cos^2(x) = 2
Rearranging the equation:
sin^2(x)+cos^2(x) -2cos(x)sin(x)=2
As,
</span><span>sin^2(x)+cos^2(x) = 1
</span><span>So,
1-2sinxcosx=2
1-1-2sinxcosx=2-1
-</span><span>2sinxcosx = 1
</span><span>Using Trignometric identities:
-2(0.5(sin(x+x)+sin(x-x))=1
-sin2x+sin0=1
As,
sin 0 = 0
So,
sin2x+0 = -1
</span><span>sin2x = -1</span><span>
2x=-90 degrees + t360
Dividing by 2 on both sides:
x=-45 degrees + t180
or 2x=270 degrees +t360
x= 135 degrees + t180 where t is integer</span>
Dude why did you scible on top of the the choices
and what is the number of children
Answer:
-11/10
Step-by-step explanation:
-7/10-2/5
-7/10-4/10
-11/10
Answer:
Step-by-step explanation:
Let the rate of boat in still water be b and the speed of the current be c
- Speed downstream = b + c
- Speed upstream = b - c
<u>We got equations for time:</u>
- 108/(b - c) = 3 ⇒ b - c = 36
- 108/(b + c) = 2 ⇒ b + c = 54
<u>Add up the equations:</u>
- b - c + b + c = 36 + 54
- 2b = 90
- b = 45 km/h
<u>Then finding the values of c</u>
Answer:
Here are some screenshots from my study guides on this, maybe they can help you.