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Question
Without using trigonometric table , evaluate :
`cos90^circ + sin30^circ tan45^circ cos^2 45^circ`
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Solution
`cos90^circ + sin30^circ tan45^circ cos^2 45^circ`
⇒ `cos90^circ + sin30^circ . sin45^circ/cos45^circ .cos^2 45^circ`
⇒ `cos90^circ + sin30^circ . sin45^circ . cos45^circ`
⇒ `0 + 1/2 . 1/2 = 1/4`
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