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AlgebraQuestion and Answers: Page 54 |
If x = log_a bc, y = log_b ca and z = log_c ab then prove that x + y + z = xyz − 2. |
In △ABC show that Σ ((1 + cos ∙ (A − B) ∙ cos C)/(h_C ∙ sec C)) = (3/(2 R)) |
if S_n =(1/(1+5n))+(1/(2+5n))+(1/(3+5n))+...+(1/(6n)), find lim_(n→∞) S_n =? |
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if xyz=1, prove ((x/(x−1)))^2 +((y/(y−1)))^2 +((z/(z−1)))^2 ≥1. |
Find: ∫_0 ^( +∞) x^𝛑 e^(−x) dx = ? |
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one solution of the equation (x−a)(x−b)(x−c)(x−d) = 9 is x=2. If a,b,c,d are different integers then a+b+c+d =? |
xp(x)=x^3 −2x^2 +x−a p(−1)=? |
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log_5 (√(5(√(5(√(5(√(5.....)))))) ))= ? |
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find the minimum value of f(x) f(x) = (√(x^2 −2x +5)) + (√(4x^2 −4x +10 )) |
Σ_(n=0) ^∞ arg(n^2 +n+1+i)= π/2 |
If → n ∈ N and n ≥ 2 Then → tan ((1/(n − 1)) Σ_(k=2) ^n arctan (1/k)) < (2/5) + (𝛄/(n − 1)) |
If → y = x ! find → (dy/dx) |
4^x =(√5^y )=400 ((xy)/(2x+y))=? |
problem 196258 (please) |
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{: ((x^(x+y) =y^(24) )),((y^(x+y) =x^6 )) }⇒(x,y)=(?,?) |
In forest , a hunter obstains that Every morning a snake eats a mouse Every afternoon a scorpion kills a snake Every night a mouse corrodes a scorpion The 8^(th) day morning , there remains Only one of them , a mouse How many were they, in each species? |
solve (√(100−x^2 ))+(√(64−x^2 ))=12 |
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Answer to the question “196008” Σ_(k=1) ^n tan^2 (((kπ)/(2n+1)))=n(2n+1) Ans) according “de moivre” sin(2n+1)α= (((2n+1)),(( 1)) )(cosα)^(2n) sinα− (((2n+1)),(( 3)) )(cosα)^(2n−2) (sinα)^3 +.... =(cosα)^(2n) (sinα)[ (((2n+1)),(( 1)) )− (((2n+1)),(( 3)) ) tan^2 α+...] for “α_k =((kπ)/(2n+1)) ; 1≤k≤n ⇒sin(2n+1)α_k =0 ⇒∀ 1≤k≤n→ (((2n+1)),(( 1)) )− (((2n+1)),(( 3)) ) tan^2 α_k +...=0 therefore “ x_k =tan^2 α_k ” thr roots of the equation are blowe x^n − (((2n+1)),((2n−1)) ) x^n + (((2n+1)),((2n−3)) )x^(n−1) −...=0 the sume of the roots of the equation is “ s= (((2n+1)),((2n−1)) ) ” ⇒s=Σ_(k=1) ^n tan^2 (((kπ)/(2n+1)))=n(2n+1)✓ the proof of the seconf part is done similarly |