Qs in complex number (1 Viewer)

rheno

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Solve:
cos^2 ax^2 +sin2ax + 1= 0


i'm just starting on complex number...can u help me solve this question, plz?
 
P

pLuvia

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Use quadratic formula and it should yield something nice

After you use the formula and simplify you should get this
x=-sin2a+icosa
 
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rheno

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i know that i should use quadratic formula, but i can not solve it......i'm really stuck ...but the answer is -tan a+- i
i dunno how to get the answer...can u plz show me???
 

Bank$

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use the sub cos^2(ax) = 1-sin^2(ax) then make it into the form:

ax^2 + bx + c=0 (with the sub that x=sinax)

then find sinax with the formula:

minus b plus or minus sq. root of b squared minus 4 times "a" times "c" over 2a.

then do the 2k(pie) thing
 

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