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# Small problem

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sqrt( cos^2(t) + sin^2(t) + (1/cos^2(t))^2 )

and I simplifed it to sqrt( 1 + (1/cos^2(t))^2 )

And what next?..

and been staring at last expressions for like 10 minutes :D, feel myself really dumb, maybe someone can help?

Guest Oct 23, 2017

#1
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sqrt( cos^2(t) + sin^2(t) + (1/cos^2(t))^2 )................(1)

Cos^2(t) + sin^2(t) =1..................................................(2)

(1/cos^2(t))^2 =(sec^2(t))^2=sec^4(t).......................(3)

Just sub (2) and (3) into (1)

Sqrt[1 + sec^4(t)]

Guest Oct 23, 2017
Sort:

#1
0

sqrt( cos^2(t) + sin^2(t) + (1/cos^2(t))^2 )................(1)

Cos^2(t) + sin^2(t) =1..................................................(2)

(1/cos^2(t))^2 =(sec^2(t))^2=sec^4(t).......................(3)

Just sub (2) and (3) into (1)

Sqrt[1 + sec^4(t)]

Guest Oct 23, 2017

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