◆ COMPLEX NUMBERS ◆
125 ( cos 288 + i sin 288 ) can be written as -
125.e^i( 288)
125.e^i( 288 +360 )
125.e^i( 288+ 720)
[ As , multiples of 360 can be added to an angle without changing any trigonometric functions or sign ]
To find the cube root , take the cube root of above 3 expressions ,
We get -
5 e^( i 96 )
5 e^( i 216 )
5 e^( i 336 )
Now using Euler's formula , We rewrite above as -
5 ( cos 96 + i sin 96 )
5(c os 216 + i sin 216 )
5 ( cos 336 + i sin 336 ) Ans.
Answer:
Let P be the external point. O be the origin. join O and P get OP and nearest point on the circle from P be A.
Let Q be the point onthe circle in which, tangent make 90° with radius at Q.
PQ = 8 and OQ = 6
we get a right angled triangle PQO right angled at Q.
so, OP^2 = OQ^2 + PQ^2= 8^2 + 6^2 = 64 + 36 =1==
therefore OP =10cm
we need nearest point from P, which is PA
PA = OP - OA= 10 -6=4cm
10g^3 - 8g^2 + 5g - 14 + 10g^2 + 12g
its just a matter of combining like terms
10g^3 + 2g^2 + 17g - 14