1. sinα = 12/13, tanα = 12/5, cosecα = 13/12
we will now solve question 2 together.
Solution to number 2
tan B = 2/3
tan2B = 4/9
tan2B + 1 = sec2B
lcm is 9
root 9 is 3
but cosB = 1/secB
since we already know tanB and cosB, we can easily get sinB using
tanB = sinB/cosB
3 cancel 3 at the denominator
divide both sides by
If cosA = 0.8, find the value of sinA and cotA.
Sin2A + cos2A = 1
Sin2A + (0.8)2 = 1
Sin2A + 0.64 = 1 (collect like terms)
Sin2A = 1 – 0.64
Sin2A = 0.36 (take the square root of both sides)
sinA = 0.6
cot A =
cot A = 1.33
we can also get our cot a from
1 + cot2A = cosec2A
1 + cot2A = (cosec2A = )
1 + cot2A = (Sin2A = 0.36 before taking the roots of both sides from above)
1 + cot2A = 2.7778
collect like terms
cot2A = 2.7778 - 1
cot2A = 1.7778
take the square root of both sides
cotA = 1.333 (same as our answer above)
Using trigonometric formulas only to solve these problems
1. If cos A = , find tan A and cosec2A
2. Given that tan B = , find the value of cos B and cosec B
3. What is the value of tan C and cos C given that sin C =
4. Given that sec2P = 1/9, find the value of cosP, sin P and cot2P
5. If cot x = 3.7, evaluate sin x, cos x and sec x.
6. What is the value of tan2 Y and sec Y when Sin Y = 2/5
7. If cot θ = 7, find the value of tan θ , sin θ and sec θ.
8. Find in terms of k sin θ and cos θ given that tan θ = k
9. If cosec α = find in terms of sec β and cot β.
10. if sec x = , what is the value of tan x and cosec x.
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