cos4thita/cos2phi+ sin 4 thita/sin2phi=1 given to prove cos4phi/cos2thita+ sin 4 phi/sin2thita plz if u provide online chating with tutor u will provide this faciliyno

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keshavkr | Student, Grade 10 | (Level 2) eNoter

Posted on

plz u solve na i think u have no idea about if u solve plz solve it is phi not pie means 22/7

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keshavgupta | Student, Grade 10 | eNotes Newbie

Posted on

it is not phi

it is phy phai now u understand or not

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giorgiana1976 | College Teacher | (Level 3) Valedictorian

Posted on

We'll re-write the condition, multiplying both sides by the least common denominator, that is the product of denominators of the terms from the left side: cos2pi*sin 2pi.

But cos 2pi = 1 and sin 2pi = 0 => cos2pi*sin 2pi = 1*0 = 0

cos 4theta/cos2pi+ sin 4 theta/sin2pi=1

(cos2pi*sin 2pi*cos 4theta)/(cos2pi)+ (cos2pi*sin 2pi*sin 4 theta)/(sin2pi)=1*cos2pi*sin 2pi

We'll reduce like terms:

sin 2pi*cos 4theta+ cos2pi*sin 4 theta =1*0

sin (2pi + 4theta) = 0

2pi + 4theta = arcsin 0

2pi + 4theta = 0

4theta = -2pi

theta = -2pi/4

theta = -pi/2

Under this conditions, we'll calculate the expression, having theta= -pi/2.

cos4pi/cos2*(-pi/2)+ sin 4 pi/sin2*(-pi/2)

cos -pi = cos pi = -1

sin -pi = -sin pi = 0

-1/-1 + 0/0

Since the second fraction is meaningless (we cannot divide by 0), the expression cannot be computed under this conditions.

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