Show that 2 (cos⁴60°+ sin⁴30°)
- (tan²60°+cot²45°)+3 sec² 30°=1/4
Answers
Answered by
6
Answer:
2(cos
4
60
∘
+sin
4
30
∘
)−(tan
2
60
∘
+cot
2
45
∘
)+3sec
2
30
∘
=[(
2
1
)
4
+(
2
1
)
4
]−[(
3
)
2
+(1)
2
]+3(
3
2
)
2
=(
16
1
+
16
1
)−(3+1)+3×
3
4
=2×
8
1
−4+4=
4
1
Answered by
1
LHS
=2 (cos⁴60°+ sin⁴30°)- (tan²60°+cot²45°)+3 sec² 30°
= {2( 1/2⁴ + 1/2⁴ )} - ( 3 + 1 ) + {3* 2²/(√3)² }
= (2 . 2/2⁴ ) - 4 + 4
= 1/4 -4 +4
= 1/4 = RHS
•°• proved
s1up_/
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