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2006-12-19 14:24:24 · 16 answers · asked by Anonymous in Science & Mathematics Mathematics

correction: (sinx+cosx)^2 + (sinx-cosx)^2 =?

2006-12-19 14:28:34 · update #1

16 answers

(sinx + cos x)^2 + (sinx - cosx)^2

= (sin^ x + cos^ x + 2 sin x cos x) + (sin^ x + cos^ x - 2 sin x cos x )

Do you know the relationship : sin^ x + cos^ x = 1

= 1 + 2 sin x cos x + 1 - 2 sin x cos x

= 2

2006-12-19 14:30:40 · answer #1 · answered by Kinu Sharma 2 · 0 1

sin^2 x + 2 * sinx * cosx + cos^2 x + sin^2x - 2 * sinx * cosx + cos^2 x = 2 * (sin^2 x + cos^2 x) = 2

2006-12-19 14:36:32 · answer #2 · answered by Rick 5 · 0 0

1 AND 2 SINX COSX = 2X, IT'S FAIRLY EASY



(sinx + cos x)^2 + (sinx - cosx)^2

= (sin^ x + cos^ x + 2 sin x cos x) + (sin^ x + cos^ x - 2 sin x cos x )

Do you know the relationship : sin^ x + cos^ x = 1

= 1 + 2 sin x cos x + 1 - 2 sin x cos x

= 2

voila :-)

2006-12-19 14:33:38 · answer #3 · answered by Anonymous · 0 0

1 and 2 sinx cosx = sin 2x... easy

2006-12-19 14:26:30 · answer #4 · answered by Anonymous · 0 1

Remember, sin^2(x) + cos^2(x) = 1

(sinx+cosx)^2 = sin^2(x) + 2*sin(x)cos(x) + cos^2(x)
(sinx+cosx)^2 = 2*sin(x)cos(x) + 1

(sinx-cosx)^2 = sin^2(x) - 2*sin(x)cos(x) + cos^2(x)
(sinx-cosx)^2 = -2*sin(x)cos(x) + 1

(2*sin(x)cos(x) + 1) + (-2*sin(x)cos(x) + 1)
1 + 1

=2

Answer: 2

2006-12-19 14:30:22 · answer #5 · answered by sft2hrdtco 4 · 0 1

(sinx+cos)^2 + (sinx-cosx)^2 = 2(sin^2x + cos^2x) = 2

2006-12-19 14:34:15 · answer #6 · answered by James Chan 4 · 0 0

(1-cosx)/sinx + sinx/(1-cosx) = ((1-cosx)(1-cosx) + (sinx)(sinx))/sinx(1-cosx) = (1-2cosx+cos^2x+sin^2x)/sinx(1-cosx) [Note: cos^2x+sin^2x=1] = (2-2cosx)/sinx(1-cosx) = (2(1-cosx))/sinx(1-cosx) = 2/sinx

2016-05-22 22:52:52 · answer #7 · answered by ? 4 · 0 0

(sinx+cosx)^2 + (sinx-cosx)^2

= (sin^2x + 2sinxcosx + cos^2x) + (sin^2x - 2sinxcosx + cos^2x)

cancel the terms which add up to zero

= sin^2x + cos^2x + sin^2x + cos^2x

which is

= (sin^2x + cos^2x) + (sin^2x + cos^2x)

and since sin^2x + cos^2x = 1
we get

= (1) + (1)
= 2

therefore,
(sinx+cosx)^2 + (sinx-cosx)^2 = 2

2006-12-19 16:48:29 · answer #8 · answered by dkrudge 2 · 0 0

sin^2 x +2sinx cosx +cos^2 x +
sin^2 x-2sinx cosx +cos^2 x=2.

2006-12-19 14:31:29 · answer #9 · answered by mathematician 7 · 1 0

(sinx+cos)^2 + (sinx-cosx)^2
=sin^2x +2sinxcosx +cos^2x + sin^2x -2sinxcosx +cos^2x
1+1 =2

2006-12-19 14:38:19 · answer #10 · answered by ironduke8159 7 · 0 0

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