Math, asked by chiragpc, 11 months ago

can you solve this problem

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Answers

Answered by tushar2788
1
it is a alegabric equation

chiragpc: algebraic and trigonometry
Answered by Anonymous
2

Answer:

a - 1/a = ±4

a³ - 1/a³ = ±76

Step-by-step explanation:

Write k = a - 1/a.

Then k² = a² - 2(a)(1/a) + 1/a² = a² + 1/a² - 2 = 18 - 2 = 16.

So k = 4 or k = -4.

Cubing k, we have

k³ = ( a - 1/a )³

= a³ - 3 a² (1/a) + 3 a (1/a)² - 1/a³

= a³ - 3a + 3/a - 1/a³

= a³ - 1/a³ - 3 ( a - 1/a )

= a³ - 1/a³ - 3 k

Hence

a³ - 1/a³ = k³ + 3k = ± ( 64 + 12 ) = ±76.


Anonymous: It's not clear to me what's meant in the trigonometric exercise. It looks like it's just asking for tan 30 times tan 60. Well, the angles add up to 90 degrees, so the product is just 1.
chiragpc: send in photo
Anonymous: ?of what? In general, if x + y = 90 degrees, then tan(x) tan(y) = 1. You can see this by drawing a right angled triangle. The side opposite the angle x is the side adjacent to angle y, and vice versa, so tan(x) = 1 / tan(y) and the product of the tans is 1.
chiragpc: answer
Anonymous: The answer is just " 1 ".
chiragpc: full with photo
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