prove the identity:2sin(45'-x)cos(45'-x)=cos2x 答案 2sin(45°-x)cos(45°-x)=sin(2*(45°-x))上式是因为倍角公式sin2x=2sinxcosx,将45°-x看成一个角.所以sin(2*(45°-x))=sin(90°-2x)=cos2x (由正弦与余弦的关系式可得)相关...
Comparing the corresponding elements, cos x = 1 and sec x = 1 These both can be true only when x = 0. Answer: x = 0.Example 2: For A = ⎡⎢⎣12−1320−402⎤⎥⎦[12−1320−402] and I is the identity matrix of order 3 x 3, prove that A · I = I · A...
Answer to: Prove the identity below: tan2x + 1 + tan x sec x = 1 + sin x cos2x. By signing up, you'll get thousands of step-by-step solutions to...
The sum and difference identities are given by: sin(α±β)=sinαcosβ±cosαsinβcos(α±β)=cosαcosβ∓sinαsinβ These equations are effective in finding the trigonometric functions for angles that can be expressed as a sum or...
解析 (sin x + sin 5x)+ (sin 2x + sin 4x)+ sin 3x LHS = (cos x + cos 5x)+ (cos 2x + cos 4x)+ cos 3x =(2sin3xcos2x+2sin3xcosx+sin3x)/(2cos3xcos2x+2cos3xcosx+cos3x) =(sin3x(2cos2x+2cosx+1)/(cos3x(2cos2x+2cosx+1))=RHS ...
Recalls a correc trig identity, which could lead to a correc answer Demonstrates a strategy for proving the identity, eg by converting all the terms on the LHS to cos and sin. Concludes a rigorous mathematical argumen to prove given identity AG (LHS=){{sin2x}\over{1+{tan}^{...
Answer and Explanation: First, let's rewrite tanx in terms of sinx and cosx. {eq}8\cos x+8\sin x\tan x\ 8\cos x +8\sin x \frac{\sin...Become a member and unlock all Study Answers Try it risk-free for 30 days Try it risk-free Ask...
Try it risk-free for 30 days Try it risk-free Ask a question Our experts can answer your tough homework and study questions. Ask a question Search AnswersLearn more about this topic: What is Trigonometry? | Functions, Formulas & Applications from Chapter 22 / Lesson 11 45K L...
Search Find an Online Tutor Now Ask a Question For Free Login Trigonometry Trigonometric Identities Identities Bree S. asked • 07/30/17 Verifying Trig identityHello! I am having some trouble verifying a trig identity sin(4x)=4cos^3(x)sin(x)-4sin^3(x)cos(x)...
(split)(LHS)&= ((sin x+sin 5x)+(sin 2x+sin 4x)+sin 3x)((cos x+cos 5x)+(cos 2x+cos 4x)+cos 3x) &= (2sin 3xcos 2x+2sin 3xcos x+sin 3x)(2cos 3xcos 2x+2cos 3xcos x+cos 3x) &= (sin 3x(2cos 2x+2cos x+1))(cos 3x(2cos 2x+2cos x+1)) &=(RHS)(spli...