Costheta+cos120-theta+cos120+theta
Answers
Step-by-step explanation:
cos(135°)-cos(120°))/cos(135°)+cos(120°)
=>
\frac{ \frac{ - 1}{ \sqrt{2}} - (\frac{ - 1}{2}) }{ \frac{ - 1}{ \sqrt{2}}- \frac{1}{2}} = > \frac{ \frac{ - 1}{ \sqrt{2} } + \frac{1}{2}}{ - \frac{1}{ \sqrt{2}} - \frac{1}{2} } = > \frac{ \frac{1 - \sqrt{2} }{2} }{ \frac{ - ( \sqrt{2} + 1)}{2}} = >
2
−1
−
2
1
2
−1
−(
2
−1
)
=>
−
2
1
−
2
1
2
−1
+
2
1
=>
2
−(
2
+1)
2
1−
2
=>
\frac{ - ( \sqrt{2} - 1)}{ - ( \sqrt{2} + 1)} = > \frac{ \sqrt{2} - 1 }{ \sqrt{2} + 1 }
−(
2
+1)
−(
2
−1)
=>
2
+1
2
−1
Rationalise the denominator
\frac{ {( \sqrt{2} - 1) }^{2} }{( \sqrt{2} + 1)( \sqrt{2} - 1)} = > {( \sqrt{2} - 1) }^{2} = >
(
2
+1)(
2
−1)
(
2
−1)
2
=>(
2
−1)
2
=>
2 + 1 - 2 \sqrt{2} = > 3 - 2 \sqrt{2}2+1−2
2
=>3−2
2