please help me with my homework
Answers
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In ∆ABD ,
Hypotenuse = 13cm
Base = 5cm
Height = x cm
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By Pythagoras theorem ,
AB^2 = BD^2 + DA^2
13^2 = X^2 + 5^2
169 - 25 = x^2
144 = x ^2
12 = x.
so , height = 12cm
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(i)Sin B = x
We know that ,sin = height/hypotenuse = p/h
Height = 12 cm
Hypotenuse = 13 cm.
so ,sin B = 12/13 cm
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In triangle ABC,
Height = 12 cm
Base = 16 cm
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(ii) tanC = y
we know that ,tan = height/base = p/b
tanC = 12/16 = 4/3cm
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In ∆ABD,
Height = 12 cm
hypotenuse = 13cm
Base = 5 cm
sec B = h/b
sec B = 13/5.
tan B = p/b
tan B = 12/5
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(iii)sec^2B - tan^2B
(13/5)^2 - (12/5)^2
169/25 - 144/25
(169 - 144)/25
25/25
= 1.
sec^2B - tan^2B = 1
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In ∆ABC,
In ∆ABC,height = 12 cm
In ∆ABC,height = 12 cmbase = 16 cm
In ∆ABC,height = 12 cmbase = 16 cmhypotenuse = 20 cm [by Pythagoras theorem]
sin C = p/h = 12/20 = 3/5 cm
cos B = b/h = 16/20 = 4/5 cm
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(iv)sin^2C + cos^2C
(3/5)^2 + (4/5)^2
9/25 + 16/25
(9 + 16)/25
25/25
1 .
sin^2C + cos^2C = 1.
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