Write the following expression in terms of the first power of the sine only. sin z + cos z I am also having trouble with this one. Please help!
y=sqrt(2)sin(x+pi/4)
How did you solve this?
replaces cosz with sqrt(1-sin^2(z))
then add the two sins together and get 2 sin x? how did you know to add π/4?
sorry wrong approach to do tht, lemme start over
sin(90-x)=cosx
sin(pi/2-x)=cosx
im so confused! i dont understand how to write it in terms of sine
um do you kno sin (a+b) , sin(a-b) formula? if u do then write cosz as sin(pi/2-z) and use the identity
oh wait i just looped u lol
lol. im trying to figure it out but its not going so well.
i just woke up im sorrygive me two minutes
ok
k i want u to imagine tht sinx+cosx is written as sinxcos(pi/4)+cosxsin(pi/4) do u kno why chose pi/4, because sin(pi/4) and cos(pi/4) both =1. now we can rewrite sinxcos(pi/4)+cosxsin(pi/4) as sin(pi/4+x)
i mean they sin(pi/4)=sqrt 2 /2 and same for cos god im sleepy lol
\[\sin(x)+\cos(x)=>\sin(x)*\cos(\pi/4)+\cos(x)\sin(\pi/4)\]
if im writing it is terms of sine then why would cosine still be there? that where im confused
sin(x)∗cos(π/4)+cos(x)sin(π/4)=1/sqrt(2)(sinx+cosx)
but it can also be written as sin(x+pi/4)=1/sqrt(2) (sinx+cosx)
bring sqrt(2) to the left hand side, by multiplying both sides sqrt2, and u get the answer =)
lemme kno what part u didnt get and ill reexplain
so the answer is sqrt(2) sin(x+π/4) = sins + cosx
does the sqrt(2) stay multiplied outside or do i multiply it to everything??
it stays outside
\[\sqrt(2) \sin(\pi/4 +x)\]
goodluck
thanks for your help!
medal?
not to be greedy or anything =P
ill give you one! but whats the answer? im still confused whats the work?
lol? i showed u the work
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